Authorities on Wednesday finished excavating and searching the grounds of Tri-State Crematory, where more than 300 corpses were discarded and left to rot.

Searchers in flat-bottom boats probed the remaining few feet of water of a lake that had been nearly drained. A skull and a torso were found earlier in the lake, but officials didn't expect to find many more remains.

Investigators began clearing and combing the 16-acre property Feb. 15 after bodies were discovered near the site. So far, 339 rotting corpses have been discovered in pits, sheds and stacked in vaults.

Crematory operator Ray Brent Marsh, 28, has been jailed on 174 counts of theft by deception for allegedly taking payment to cremate the dead and instead passing off cement powder and dirt as human ashes.

Dr. Kris Sperry, chief medical examiner, said 108 corpses have been identified.

Sperry, who earlier had said some remains appeared at least a decade old, said Wednesday he didn't know whether any corpses were older than 1997.

Marsh, who took over the crematory from his father in 1996, has told investigators the incinerator was broken. Tests earlier this week showed the incinerator was working properly.