SAN FRANCISCO - Firefighters are battling a four-alarm fire burning in a building along San Francisco's waterfront.

A San Francisco Fire Department dispatcher says the blaze in a building on Pier 29 was reported at 1:50 p.m. Wednesday. It's not known what sparked the fire. So far, no injuries have been reported.

Large flames and thick black smoke are coming from the building. The pier is is located on The Embarcadero, near Chestnut and Lombard streets.

Traffic has been stopped along the roadway, which is a main route along the city's waterfront.