The San Francisco Police Department is investigating an incident caught on video that shows an officer apparently forcing a handcuffed woman face first into the pavement.

In the video, shot by a bystander and posted on YouTube before being removed, the belligerent woman - who police said was drunk and pushing a baby in a stroller - shouts obscenities at two Taraval Station officers attempting to arrest her Sunday afternoon.

The woman can be seen resisting both officers' efforts to place her in the police car. The baby, left in the stroller on the sidewalk, can be heard crying. The officers almost manage to get the woman into the unit, but she pushes against the car and yells, "It's my baby in the street!"

While one officer goes to the other side of the patrol car, the other is left to deal with the woman alone. The video shows him bracing her neck with his hand as she pushes back to avoid getting into the car.

Then, the officer appears to move to the side and grunt as he appears to push the woman face first into the pavement on the street between two parked cars.

In the police report, the officer gave a version of what occurred and acknowledged that he used force against the woman, authorities say. The officers stopped the woman because they believed she was the suspect in an assault they were responding to, police said.

Although not shown on the video, an ambulance soon arrived and took the woman to San Francisco General Hospital. She bit one of the paramedics on the way, according to police accounts.

"We want to make sure we have a full understanding of what occurred, and we obviously are going to take whatever action that is appropriate," Chief George Gascón said.

The unidentified six-year veteran Taraval Station officer was ordered to surrender his badge and weapon on Monday, pending the outcome of an internal investigation into the incident, authorities said Tuesday.

Assistant Police Chief Jeff Godown said one issue in the investigation is that the woman was handcuffed - and under police authority - at the time of the incident.

"The bottom line, we will take a look at it and see what happened," Godown said. "We're reviewing the videotape and the use of force report to determine whether the use of force was necessary."

Godown said the officer has been reassigned to non-field duty pending the outcome of the probe.

The video can be viewed at sfgate.com/ZJZZ.