OAKLAND, Calif. » Authorities say two San Francisco officers are hurt as a result of a protest over the Ferguson shooting, and police have made arrests.

The violence occurred Friday around 9:30 p.m. (7:30 p.m. Hawaii time) after hundreds of protesters marched through downtown packed with Black Friday shoppers to protest the Missouri shooting of a black man by a white police officer.

Sgt. Monica Macdonald says one of the officers was taken to a hospital after a protester threw bottle at a police car and the officer’s face was cut by flying glass. Another officer was struck in the chest by a brick.

Macdonald says police have begun making arrests, but she says it’s too early to know how many.

Earlier in the evening, the crowd marched through the heart of the city’s shopping district and arrived at Union Square, where police stopped them from disrupting the lighting of a Christmas tree in the popular area.

The crowd then went to the Mission District.