Los Angeles police launched an internal investigation Friday after an attorney released body camera video that he says shows an officer planting cocaine in his client's wallet during an arrest.

The video was taken during an arrest in April when officers stopped Ronald Shields, 52, who they suspected had been involved in a hit-and-run crash.

It appears to show an officer standing beside Shields, who is in handcuffs, as another officer leans down and picks up a small baggie filled with white powder — which later tested positive for cocaine — that is on the ground. The officer who picked up the baggie then motions to the second officer, points to Shield's wallet in his hand and appears to place the baggie in the wallet.

The officer then turns on his body camera, but the cameras automatically save the previous 30 seconds when they are switched on.

"The drugs were certainly planted," Shields' attorney, Steve Levine, said. "If not for the body cam video, my client would be convicted of a crime he didn't commit."

Los Angeles police said they opened an investigation after the body camera video was aired by KCBS-TV on Thursday.

"The LAPD takes all allegations of misconduct seriously and, as in all cases, will conduct a thorough investigation to determine whether the alleged actions are supported by reliable evidence," police said in a statement.

Levine is asking a judge to suppress the evidence. The Los Angeles County district attorney's office did not immediately respond to a request for comment.