The protest started around 7:45 a.m. and no cars were able to get into San Francisco for hours. Westbound lanes of the bridge could be seen empty as traffic backed up and all lanes didn't reopen until just before noon.
Images show cars blocking the lanes on the eastern span of the bridge as the protesters call for a cease-fire in the Middle East.
VIDEO: Were authorities caught off guard by Bay Bridge protest? SF sheriff weighs in
Were authorities caught off guard by Bay Bridge protest?
Protesters were lying down with white sheets over their bodies that said "Stop the genocide."
They were also holding up large banners that said "Stop the genocide. No US military aid to Israel."
At least 15 cars were towed.
They said that the protesters parked their cars on the bridge and threw their keys into the bay.
PHOTOS: Bay Bridge shutdown to San Francisco protests for APEC 2023
CHP said that the protesters were spread throughout the traffic, making it difficult to clear the scene. CHP officers were going car by car to find ones that were abandoned.
The protest was in response to world leaders including President Biden being in San Francisco this week for the APEC summit.
Mom driving into SF for work among dozens arrested
One of those arrested was a mom that was stuck in traffic headed into San Francisco for work.
"I told my kids. I called them and said, hey there is a protest and they said, 'mama that is history go film it.' So I got out of my car and started filming it and saw that police were being very pushy with the protestors," said Petra Luber, Oakland resident
Petra Luber said she was arrested after shooting video of CHP officers pushing protestors.
"He said, 'you gotta move out of the way' and I couldn't because there was a car behind me and I said, hold on and then he grabbed and arrested me," said Luber.
Bay Bridge shutdown brings East Bay traffic to standstill for hours
Bay Bridge protest brings East Bay traffic to standstill for hours
The shutdown of the upper deck of the Bay Bridge lasted several hours on Thursday morning, which led to massive backups and traffic delays in the East Bay during the morning commute. Many commuters were stuck in their cars for hours.
Emeryville police spent hours directing traffic as the on-ramp to westbound 80 was closed because of the bridge closure. Some commuters tried their luck on city streets, but were also stuck.
"For me, (traffic) has been hell," says Lydia Navarro, a Santa Rosa resident. She spent two and half hours on her commute.
It wasn't just commuters stuck in traffic. UCSF tells ABC7 News that three couriers trying to deliver organs for transplants were also caught in the delays. At least one surgery was canceled.
VIDEO: 'Stop Bombing Children': Israel-Gaza cease fire message projected on SF's Ferry Building
'Stop Bombing Children': Israel-Gaza cease fire message projected on SF's Ferry Building
"We expect there will be more problems with patients in the afternoon who are trying to arrive now for surgery," explains Garrett Roll, Associate Professor of Transplant Surgery at UCSF.
And there were those who just parked along roads in Emeryville, waiting for the Bay Bridge to reopen.
"People are out here honking, and turning around, and watching and wondering," say Teresa Knight, who lives in Richmond.
The California Highway Patrol say the Bay Bridge reopened around 12:00 p.m.