DENVER – Paleontologists say fossilized bones unearthed at a suburban Denver construction site are those of a large adult triceratops.

Maura O’Neal, a spokeswoman for the Denver Museum of Nature & Science, said Friday the partial skeleton included a limb bone and several ribs of the three-horned dinosaur.

The Denver Post reports the bones were found at a construction site near a retirement community in Highlands Ranch in May in a rock layer that dates back 65 million to 68 million years.

Construction crews are using heavy equipment to dig a deep trench in search for other dinosaur fossils next to the area where the triceratops bones were found. O’Neal says that of all the dinosaur bones discovered in Colorado, the remains of triceratops have been among the most common.