SAN FRANCISCO (CBS SF) – A four-car chain reaction accident on the Bay Bridge early Thursday triggered a traffic nightmare for commuters traveling into San Francisco.

The California Highway Patrol reported that the incident began with the collision between a black Jeep SUV and a Toyota RAV just west of the Yerba Buena Island tunnel at 7:38 a.m.

Two other vehicles became involved in the crash shutting down three lanes and backing up the morning rush hour traffic.

At least 30-45 minutes was being added to the commute into the city.

The CHP was advising motorists to take San Mateo Bridge as an alternate.