BISHOP, Calif. — Rock carvings that graced a sacred American Indian site in California's Sierra Nevada for thousands of years have fallen prey to modern thieves armed with power saws.

At least four petroglyphs – some 2 feet wide and located 15 feet above the ground – were hacked from lava cliffs in the Eastern Sierra, the Los Angeles Times ( ) reported Sunday. http://lat.ms/Q3YdXQ

Visitors to the area, known as Volcanic Tableland, discovered the theft and reported it to the federal Bureau of Land Management on Oct. 31.

"This was the worst act of vandalism ever seen" on the 750,000 acres of public land administered by the BLM field office in Bishop, BLM archaeologist Greg Haverstock told the newspaper....