CLAYTON - St. Louis County police have conducted an investigation into one of its own after allegations of an assault on a prisoner surfaced in July.

A prisoner alleged that a county officer physically assaulted him when he was in custody at the West County precinct on July 18. The officer was working as a convenyance officer at the time and has since retired, said Officer Rick Eckhard.

Eckhard would not say how long the officer had worked for the department nor reveal the date of his retirement in relation to the incident.

County police then launched an investigation into the allegations and turned in its findings last week to the county prosecutor's office, Eckhard said. Among the evidence presented was surveillance footage from cameras mounted in the room where the alleged assault took place, Eckhard said.

Eckard characterized the incident as a third-degree assault, which means no weapons were used and injuries are non-lifethreatening. He would not confirm whether the alleged victim was injured.

The officer will not be named unless charges are filed.