The site of a major dinosaur-fossil discovery near Hanksville was vandalized and at least two bones were stolen, the Bureau of Land Management said Thursday.

An excavation team from Rockford, Ill., unearthed a number of fossils in a preserved river channel earlier this summer, and scientists believed the find would go a long way toward understanding the world 145 million years ago.

But with the vandalism of the site and theft of two bones, researchers are now missing "another piece of the puzzle," said Scott Foss, the BLM's regional paleontologist.

"It's a large scientific loss," Foss said. "And there's very small gain to be had on their (the thieves') side."

A team from the Burpee Museum of Natural History spent several weeks excavating the quarry but returned to Illinois in July without finishing the dig, Foss said. The team covered exposed fossils with jackets of burlap and plastic and buried the site to protect the discoveries until the team returned next summer.

Earlier this month, BLM officials discovered two of those jackets had been vandalized. The rib from a large dinosaur and an allosaurus bone had been stolen from the site.

The thieves "left a lot of bone," Foss said. "It wasn't very sophisticated."

Foss said the bones were not in great condition and would not fetch much money if sold. But for scientists, the pieces are priceless, he said.

The quarry's location has not been made known to the public because BLM officials want to develop the area for educational and recreational opportunities, Foss said. But the site was well-known to locals, he said.

If the bones are returned, scientists could use them in their efforts to put together a complete dinosaur, Foss said. Anyone with information is asked to contact the BLM at 801-539-4133.

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