HRABOVE, Ukraine – Ukraine accused pro-Russian separatists of shooting down a Malaysian jetliner with 298 people aboard Thursday, sharply escalating the crisis and threatening to draw both East and West deeper into the conflict. The rebels denied downing the aircraft.

American intelligence authorities believe a surface-to-air missile brought the plane down, but they were still working on who fired the missile and whether it came from the Russian or Ukrainian side of the border, a U.S. official said.

Bodies, debris and burning wreckage of the Boeing 777 were strewn over a field near the rebel-held village of Grabove in the Donetsk region of eastern Ukraine, about 25 miles from the Russian border, where fighting has raged for months.

U.S. Vice President Joe Biden described the plane as having been “blown out of the sky.”

The aircraft appeared to have broken up before impact, and there were large pieces of the plane that bore thered, white and blue markings of Malaysia Airlines – now familiar worldwide because of the carrier’s still-missing jetliner from earlier this year.

The cockpit and one of the turbines lay at more than a half-mile from one another. Residents said the tail was about six miles farther away. Rescue workers planted sticks with white flags in spots where they found human remains.

There was no sign of any survivors from Flight 17, which took off shortly after noon Thursday from Amsterdam to Kuala Lumpur with 283 passengers, including three infants, and a crew of 15. Malaysia’s prime minister said there was no distress call before the plane went down and that the flight route was declared safe by the International Civil Aviation Organization.

President Petro Poroshenko called it an “act of terrorism” and demanded an international investigation. He insisted his forces did not shoot down the plane.

Ukraine’s security services produced what they said were two intercepted telephone conversations that showed rebels were responsible. In the first call, the security services said, rebel commander Igor Bezler tells a Russian military intelligence officer that rebel forces shot down a plane. In the second, two rebel fighters – one of them at the crash scene – say the rocket attack was carried out by a unit of insurgents about 15 miles north of the site.

Neither recording could be independently verified.

Earlier in the week, the rebels had claimed responsibility for shooting down two Ukrainian military planes.

President Barack Obama called the crash a “terrible tragedy” and spoke by phone with Russian President Vladimir Putin as well as Poroshenko. Britain asked for an emergency meeting of the U.N. Security Council on Ukraine.

Later, Putin said Ukraine bore responsibility for the crash, but he didn’t address the question of who might have shot it down and didn’t accuse Ukraine of doing so.

“This tragedy would not have happened if there were peace on this land, if the military actions had not been renewed in southeast Ukraine,” Putin said, according to a Kremlin statement issued early today. “And, certainly, the state over whose territory this occurred bears responsibility for this awful tragedy.”

At the United Nations, Ukrainian Ambassador Yuriy Sergeyev told the AP that Russia gave the separatists a sophisticated missile system and thus Moscow bears responsibility, along with the rebels.

Officials said more than half of those aboard the plane were Dutch citizens, along with passengers from Australia, Malaysia, the United Kingdom, Germany, Belgium, the Philippines and Canada. The home countries of nearly 50 were not confirmed.

The different nationalities of the dead would bring Ukraine’s conflict to parts of the globe that were never touched by it before.

Ukraine’s crisis began after pro-Moscow President Viktor Yanukovych was driven from office in February by a protest movement among citizens angry about endemic corruption and seeking closer ties with the European Union. Russia later annexed the Crimean Peninsula in southern Ukraine, and pro-Russians in the country’s eastern regions began occupying government buildings and pressing for independence. Moscow denies Western charges it is supporting the separatists or sowing unrest.

Kenneth Quinn of the Flight Safety Foundation said an international coalition of countries should lead the investigation. Safety experts say they’re concerned that because the plane crashed in an area of Ukraine that is in dispute, political considerations could affect the investigation.

The RIA-Novosti agency quoted rebel leader Alexander Borodai as saying talks were underway with Ukrainian authorities on calling a short truce for humanitarian reasons. He said international organizations would be allowed into the conflict-plagued region.

Some journalists trying to reach the crash site were detained briefly by rebel militiamen, who were nervous and aggressive.

Aviation authorities in several countries, including the FAA in the United States, had issued warnings not to fly over parts of Ukraine before Thursday’s crash, but many carriers, including cash-strapped Malaysia Airlines, had continued to use the route because “it is a shorter route, which means less fuel and therefore less money,” said aviation expert Norman Shanks.

Within hours of Thursday’s crash, several airlines said they were avoiding parts of Ukrainian airspace.

Malaysia Airlines said Ukrainian aviation authorities told the company they had lost contact with Flight 17 at 1415 GMT (10 a.m. EDT) about 20 miles from Tamak waypoint, which is 30 miles from the Russia-Ukraine border.

A U.S. official said American intelligence authorities believe the plane was brought down by a surface-to-air missile, but were still working to determine additional details about the crash, including who fired the missile and whether it came from the Russian or Ukraine side of the border.

But U.S. intelligence assessments suggest it is more likely pro-Russian separatists or the Russians rather than Ukrainian government forces shot down the plane, according to the official, who spoke on condition of anonymity because he was not authorized to discuss the matter publicly.

The U.S. has sophisticated technologies that can detect missile launches, including the identification of heat from the rocket engine.

Anton Gerashenko, an adviser to Ukraine’s interior minister, said on his Facebook page the plane was flying at about 33,000 feet when it was hit by a missile from a Buk launcher, which can fire up to an altitude of 72,000 feet. He said only that his information was based on “intelligence.”

Igor Sutyagin, a research fellow in Russian studies at the Royal United Services Institute, said Ukrainian and Russian forces have SA-17 missile systems – also known as Buk ground-to-air launcher systems.

Rebels had bragged recently about having acquired Buk systems.

Sutyagin said Russia had supplied separatists with military hardware, but had seen no evidence “of the transfer of that type of system from Russia.”

Earlier Thursday, AP journalists saw a launcher that looked like a Buk missile system near the eastern town of Snizhne, which is held by the rebels.

Poroshenko said his country’s armed forces didn’t shoot at any airborne targets.

“We do not exclude that this plane was shot down, and we stress that the Armed Forces of Ukraine did not take action against any airborne targets,” he said.

The Kremlin said Putin “informed the U.S. president of the report from air-traffic controllers that the Malaysian plane had crashed on Ukrainian territory” without giving further details about their call. The White House confirmed the call.

Separatist leader Andrei Purgin told the AP he was certain that Ukrainian troops had shot the plane down, but gave no explanation or proof.

Purgin said he did not know whether rebel forces owned Buk missile launchers, but said even if they did, they had no fighters capable of operating them.

In Kuala Lumpur, several relatives of those aboard the jet came to the international airport.

A distraught Akmar Mohamad Noor, 67, said her older sister was coming to visit the family for the first time in five years. “She called me just before she boarded the plane and said ‘see you soon,’” Akmar said.

It was the second time a Malaysia Airlines plane was lost in less than six months. Flight 370 disappeared in March en route from Kuala Lumpur to Beijing. It has not been found, but the search has been concentrated in the Indian Ocean far west of Australia.

There have been several disputes about planes being shot down over eastern Ukraine in recent days.

A Ukrainian fighter jet was shot down Wednesday by an air-to-air missile from a Russian plane, Ukrainian authorities said, adding to what Kiev says is mounting evidence that Moscow is directly supporting the insurgents. Ukraine Security Council spokesman Andrei Lysenko said the pilot of the Sukhoi-25 jet hit by the missile bailed out after his jet was hit.

Moscow’s U.N. Ambassador Vitaly Churkin denied Russia shot down the Ukrainian fighter jet.

Pro-Russia rebels claimed responsibility for strikes on two Ukrainian Sukhoi-25 jets Wednesday.

Ukraine’s Defense Ministry said the second jet was hit by a portable surface-to-air missile, but the pilot landed safely.

Earlier this week, Ukraine said a military transport plane was shot down Monday over eastern Ukraine by a missile from Russian territory.

Peter Leonard reported from Kiev with contributions from an Associated Press reporter in Hrabove, Ukraine. Also contributing were AP Airlines Writer Scott Mayerowitz in New York; Jill Lawless and Matthew Knight in London; Laura Mills and Jim Heintz in Moscow; Lolita C. Baldor and Darlene Superville in Washington; Edith M. Lederer at the United Nations; Mike Corder in The Hague, Netherlands; and Eileen Ng and Satish Cheney in Kuala Lumpur, Malaysia.

Disaster strikes twice

HANOI, Vietnam – Two Boeing 777s. Two incredibly rare aviation disasters. And one airline.

In what appears to be a mind-boggling coincidence, Malaysia is reeling from the second tragedy to hit its national airline in less than five months.

On March 8, a Malaysia Airlines jetliner vanished about an hour after taking off from Kuala Lumpur, spawning an international mystery that remains unsolved. On Thursday, the airline – and the nation – were pitched into another crisis after the same type of aircraft was reported shot down over Ukraine.

Ukraine said the plane was brought down by a missile over the violence-wracked eastern part of the country. Other details were only just beginning to emerge.

But what’s certain is that the struggling airline and the nation must now prepare for another agonizing encounter with grief, recriminations, international scrutiny and intense legal and diplomatic implications.

Amid it all, a question: Just how could disaster strike the airline twice in such a short space of time?

“Either one of these events has an unbelievably low probability,” said John Cox, president and CEO of Safety Operating Systems and a former airline pilot and accident investigator. “To have two in a just a few months of each other is certainly unprecedented.”

The first disaster deeply scarred Malaysia and left the world dumbstruck. How could a Boeing 777-200ER, a modern jumbo jet, simply disappear? Flight 370 had veered off course during a flight to Beijing and is believed to have crashed in the Indian Ocean far off the western Australian coast.

The search area has changed several times, but no sign of the aircraft, or the 239 people aboard, has been found. Until then, how the plane got there is likely to remain a mystery.

On Thursday, there was no mystery over the whereabouts of the Boeing 777-200ER, which went down while on a flight from Amsterdam to Kuala Lumpur with 280 passengers and 15 crew members. Its wreckage was found in Ukraine, and there were no survivors.

Officials said the plane was shot down at an altitude of 33,000 feet. The region has seen severe fighting between Ukrainian forces and pro-Russia separatists in recent days.

Malaysia Airlines was widely criticized for the way it handled the Flight 370 hunt and investigation. Some relatives of those on board accused the airline of engaging in a cover-up, and there have been persistent conspiracy theories over the fate of the plane, including that it might have been shot down.

There was no immediate reason to think the two disasters to befall the airline were in any way linked.

Cox said that to his knowledge, there was no prohibition against flying over eastern Ukraine despite the fighting on the ground. He said that if the plane was shot down by a missile, the pilot probably did not even know it.

“A missile like this typically closes in from behind, there is no reason for him to have seen it,” he said.

Charles Oman, a lecturer at the department of aeronautics and astronautics at the Massachusetts Institute of Technology, said it was too early to draw conclusions. He said terrorism was one possible consideration, but said that the security out of Amsterdam was competent.

“Given the military conflict in the region, one has to be concerned that identities could have been mistaken,” he said in an email.

Malaysia Airlines was especially criticized for the way it handled the communications around the missing jetliner, which presented unique challenges because of the uncertainty facing the relatives of those on board. With the plane crashing Thursday over land and its wreckage already located, there will be no such uncertainty.

But the investigation will be just as sensitive. There will be legal and diplomatic implications depending on who was responsible.

“The airline and the Malaysian Transport Ministry took a lot of hits for the way they handled MH370, due to their inexperience,” Oman said. “Hopefully they will do better this time.”

The accident will surely inflict more financial damage on Malaysia Airlines. Even before the March disaster, it reported losses because of stiff competition from budget airlines. Afterward, passengers canceled flights, and even though the airline is insured, it faces uncertainty over payouts to the victims’ families.