IOWA HILL, Calif. - Alone in the woods with his left leg pinned beneath a fallen tree for 11 hours, a 66-year-old man used pocket knives to cut off his limb below the knee to free himself, a neighbor and authorities said.

Al Hill had been cutting trees last Friday when one fell on him. After freeing himself, he cried out for help, and a neighbor passing through this sparsely populated area heard him.

Eric Bookey then hiked nearly two miles to get a cellular signal and placed an emergency call to the town's all-volunteer fire department about 7:30 p.m., Fire Chief Luana Dowling told The Associated Press on Wednesday.

Hill was eventually airlifted by helicopter to a hospital where he underwent amputation surgery, Dowling said. "He's a pretty remarkable person," Dowling said.

A hospital spokeswoman said Hill was in serious condition on Wednesday, and that he was declining interviews.