Media playback is unsupported on your device Media caption Video shows officer body slamming girl

A Texas school police officer who was shown body slamming a 12-year-old girl in a mobile phone video has been fired.

The footage shows officer Joshua Kehm restraining Janissa Valdez and then throwing her to the ground.

Her classmates are heard saying in the video: "She landed on her face" and "Janissa! Janissa, you OK?"

The incident happened on 29 March at a school in San Antonio, but the video was first published on a local blog last week.

The San Antonio Independent School District had placed Mr Kehm on paid leave after the incident, but on Monday announced that he was fired "effective immediately".

"We understand that situations can sometimes escalate to the point of requiring a physical response; however, in this situation we believe that the extent of the response was absolutely unwarranted," Superintendent Pedro Martinez said.

Mr Kehm could not be immediately reached for comment.

The school district has referred the incident to law enforcement to determine whether criminal charges are warranted.

Janissa Valdez's mother, Gloria, acknowledged her daughter had been fighting with another classmate but said Janissa suffered swelling to her temple.

"I talked to the officer. He did what he had to do at the moment - those were his words," Mrs Valdez told a local TV station.

Almost 31,000 police officers are based at US public schools, recent figures show.

Last year, a school resource officer was fired in South Carolina after he was seen throwing a female student across a classroom.