Police say their ShotSpotter -- a gunshot location system -- activated near Laguna and Page streets. They said they also got reports of a car crash.
A lot of bullets flew on Laguna Street and some homes were hit. One bullet ended up lodged in someone's refrigerator.
There is no description of the suspect or suspects involved. Police don't know if there was more than one shooter or what the motive was.
SFPD confirm 4 people dead in shooting in Hayes Valley. #mapit @abc7newsBayArea pic.twitter.com/W1suPlHR4F
— Katie Marzullo (@KatieABC7) January 10, 2015