SAN FRANCISCO (KRON) — San Francisco police are looking for a woman suspected of assaulting and robbing a 71-year-old taxi driver late Thursday night.

Investigators said a cab was called to the Potrero Terrace public housing complex in the city’s Potrero Hill neighborhood at about 10:45 p.m.

The passenger requested to be dropped off in the 1000 block of Palou Avenue in the city’s Bayview District, according to police spokesman Officer Albie Esparza.

Police said when the taxi arrived to the destination, the woman grabbed the driver from behind. She then put him in a headlock and cut his face with a knife and demanded money, according to Esparza.

The victim struggled with the suspect, before she took off with the driver’s cell phone and cash.

The suspect is described as a black woman weighing 250 pounds, about 5 feet 7 inches tall, and between 27 and 33 years old. Police said she was wearing a black shirt and black pants.

Police are working to find the woman. They have a major lead in the case because investigators have the contact information she used to request the cab, according to Esparza.

Police said the cab driver suffered minor lacerations to his face, but declined to be transported to the hospital.