A 56-year-old man from Tucson died Wednesday while digging for rocks near St. David.

William T. Lawrence and a friend were in a wash southeast of Benson digging for rocks and minerals just before 1 p.m. when the wall of the wash collapsed, trapping Lawrence under debris, Carol Capas, spokeswoman for the Cochise County Sheriff’s Department, said in a news release.

His 70-year-old companion had to hike out of the wash and flag down a passing motorist for help, Capas said.

“The woman … heard a noise and when she looked towards her friend, there was a large pile of debris and rock where he had been standing,” Capas said.

It took four hours to dig Lawrence’s body out of the rubble, Capas said.