LOS ANGELES, July 5 (Reuters) - California Highway Patrol is investigating a video showing an officer pummeling a woman alongside a Los Angeles freeway during an arrest that began with an attempt to stop her from walking into traffic, an agency spokeswoman said on Saturday.
The video, which was taken by a passing motorist, posted online and broadcast by local television stations, has caused an outcry from community activists who say the officer used excessive force in the arrest on Tuesday.
Officials from the Highway Patrol on Friday became aware of the video, which captures an incident that occurred on Interstate 10 in Los Angeles, and they have launched a use of force investigation, Sergeant Denise Joslin, an agency spokeswoman, said in an email.
"We're looking at every possibility, every fact, every circumstance that have contributed to this situation and we're going to try to come to a just conclusion," Highway Patrol Assistant Chief Chris O'Quinn said at a news conference on Friday.
The officer arrived at the location after the Highway Patrol received a call about a woman walking by the side of the freeway, a statement from the Highway Patrol said.
After spotting the woman walking shoeless along the narrow shoulder of the freeway and stepping into traffic lanes, the officer told her to stop, the statement said. When the officer approached the woman she became "physically combative" and he arrested her in fear of her safety and his own, it said.
The video from the passing motorist shows the officer pull the woman to the ground at the edge of the freeway and straddle her, as he repeatedly punches her in the head.
Another man is seen in the video running up and helping the arresting officer. The Highway Patrol statement described that man as an off-duty police officer who helped the Highway Patrol officer put handcuffs on the woman.
Earl Ofari Hutchinson, founder of the Los Angeles Urban Policy Roundtable, and other local community activists criticized the arrest.
"Excessive force, abuse of authority, is not going to be tolerated," Hutchinson said at a news conference.
Joslin did not say if the officer was placed on leave or allowed to continue working.
The woman, whose name was not released, was hospitalized for evaluation but did not appear to have any physical injuries, Highway Patrol officials said. (Reporting by Alex Dobuzinskis; Editing by Barbara Goldberg and Diane Craft)