A doctor has pleaded guilty to two felonies involving removal of ancient Native American artifacts from public lands in California and Nevada.

Anesthesiologist Jonathan Bourne of Mammoth Lakes entered his plea Monday in Fresno federal court.

The Los Angeles Times reports federal authorities began investigating after a hiking club website published photos of Bourne digging a wooden bow out of a melting glacier in the Sierra Nevada.

Bourne was indicted last year on numerous counts involving archaeological resources crimes.

But under a plea agreement Bourne admitted to unlawfully removing glass trade beads from a site in the Humboldt-Toiyabe National Forest in Nevada.

He also admitted he altered a site in Death Valley National Park by removing a tool made from a bighorn sheep horn and three etched stone tablets.