Police and fire are on the scene, as well as Coast Guard helicopters.
A witness on the scene is reporting she saw young people wearing blankets who appeared to have been rescued from the water.
PIER 45 BOAT CAPSIZED WITH ABOUT 30 JUV ON BOAT SOME ARE TRAPPED UNDER THE HULL. USCG BOAT/HELIO/DIVERS EN ROUTE. pic.twitter.com/KnEKFVgpjx— San Francisco Fire (@sffdpio) October 8, 2016