Four of the firefighters were hospitalized and one will remain there overnight after suffering hypothermia. An investigation is now underway into what caused the incident.
It happened during a routine training exercise near the Cliff House. Seven firefighters were aboard a 30-foot rescue fire boat when they got into trouble.
"Conditions were calm, as I understand it. What I do understand there was a big wave that came up, what some might call a rogue wave came and flipped the boat," said San Francisco Deputy Fire Chief Mark Gonzales.
The firefighters were tossed into the chilly water. Firefighters on jet skis were nearby, but rescuing everyone was tough.
"We thought that maybe somebody was dropped on the rocks and we couldn't see them on the backside, or maybe they had gone under gone under," said Joseph Cole, a witness.
Sky7 was over Lands End where the boat drifted, along with equipment that was on board that floated on the water.
"We've had some of our most experience firefighters and swimmers were on that boat," Gonzales said. Gonzales said the most important thing is that all members are OK after a scary day on the water.
#UPDATE: Victims of overturned boat were part of SF Fire Dept conducting a training mission. All 7 victims are safe and accounted for.— ABC7 News (@abc7newsBayArea) March 26, 2016
JUST IN: Coast Guard safely rescues all victims from a boat that overturned near Ocean Beach in SF.— ABC7 News (@abc7newsBayArea) March 26, 2016