Providence Mayor Jorge Elorza is calling for an investigation after a cellphone video surfaced showing a police officer punching and dragging a woman.

Elorza said Friday that after watching the video he has directed the city's police chief and public safety commissioner to investigate what happened.

Public Safety Commissioner Steven Pare (PAH'-ree) says the video shows police responding to a disturbance outside a home in the early morning hours of May 23.

A police report describes a tense scene on the porch outside the home and a physical struggle between police officers and people they say were combative. A patrolman went to the hospital after being bitten.

Pare says he first became aware of the incident Thursday after the video was obtained by media outlets.