01/17/2014 01:40 pm ET Updated Jan 25, 2014

David DiPaolo Accused Of Killing Rock Climbing Friend With Claw Hammer

It looked like a well-known rock climber found bleeding from the head at the bottom of a Maryland cliff had fallen, but federal prosecutors allege his friend killed him in a fight.

Geoffrey Farrar, 69, died after being airlifted from Chesapeake & Ohio Canal National Historical Park to a hospital three days after Christmas, the Washington Post reported. An autopsy disproved the assumption he died in a bouldering accident.

About three weeks later, his climbing protégé David DiPaolo allegedly admitted to striking Farrar with a claw hammer in self-defense, NBC Washington reported.

DiPaolo, 31, told authorities that Farrar, was choking him, ABC News reported. To free himself from his mentor's grasp, he hit him with the tool that's widely used by climbers.

The pair had argued earlier in the day in the parking lot of the Carderock section of the park, according to DiPaolo's statement to investigators. Later, when DiPaolo encountered Farrar on the trail, the accused killer said that Farrar wrestled him to the ground and choked him.

Farrar took DiPaolo under his wing almost two decades ago, the Washington Post said. Many local climbers knew Farrar, according to the Post, which reported that he frequently gave advice to newcomers to the sport.

Witnesses who found Farrar's mortally wounded body reported seeing DiPaolo running away moments before the grim discovery, Fox's D.C. affiliate reported. He fled to Glen Falls, N.Y., where he was arrested Jan. 8 and charged with manslaughter.

DiPaolo reportedly agreed to be sent back to Maryland for a trial.