San Francisco firefighters were responding to a wall collapse in the Bernal Heights neighborhood late Tuesday morning.
The collapse was reported at 501 Crescent Ave. just after 10 a.m., according to a fire department spokesman.
The two-story residential building is currently under construction. No injuries have been reported, fire officials said.
The Department of Building Inspection has been called to the scene.
No street closures have been announced but residents were being asked to avoid the area.