A police officer filmed wrestling a girl (14) wearing a bikini to the ground at a pool party has resigned.

Officer David Eric Casebolt has left the McKinney Police Department in Texas after almost 10 years on the force.

The move follows the release of a video showing him pushing the teenager and pinning her down, and brandishing his gun at others.

He and other officers were responding to complaints about the party at a community-owned pool.

McKinney Police Chief Greg Conley had placed the 41-year-old on administrative leave after the incident.

Police Chief Greg Conley confirmed the resignation at a news conference later on Tuesday, saying Officer Casebolt had not been pressured to quit.

Mr Conley said a review of the video showed Officer Casebolt's actions were "indefensible," and that "our policies, our training and our practices do not support his actions".

In all, 12 officers responded to the report of fights and a disturbance at the pool party at the Craig Ranch North Community Pool.

"Eleven of them performed according to their training," Mr Conley added.

"He came into the call out of control and the video showed he was out of control during the incident."

Despite Officer Casebolt's resignation, his actions remain under investigation and no decision has been made as to whether charges will be filed against him.