Rangers are searching for leads after someone damaged a fossil at Dinosaur National Monument along the Utah-Colorado line.

The National Park Service says a ranger leading a guided tour Tuesday discovered damage to the fossilized humerus bone of a sauropod dinosaur and removal of part of the bone.

The fossil is among those located along the 1.2-mile Fossil Discovery Trail that runs between the Quarry Visitor Center and the Quarry Exhibit Hall, where a famous wall of about 1,500 dinosaur bones is located.

All fossils in the monument are protected and may not be collected.

A $750 reward is being offered for information leading to a conviction in the case.

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