SAN FRANCISCO (CBS SF) — A crash inside the Douglas MacArthur tunnel blocked all southbound lanes of Highway 1 Friday afternoon, causing severe traffic delays near San Francisco’s Golden Gate Park.

CalTrans posted about the crash on social media, stating that it occurred around 3:51 p.m., according to the California Highway Patrol (CHP).

READ MORE: Thieves Target License Plates in San Francisco; Rack Up Parking Tickets

“Motorists are advised to expect delays and to use alternate routes to avoid the area,” Caltrans noted. “There is no estimated time to reopen the roadway.”

READ MORE: Fans Remember Betty White With Challenge To Fund Animal Shelters

Despite the crash being on the Southbound lanes, it caused delays in both directions, reaching as far as the Golden Gate Bridge, with northbound delays stretching onto Park Presidio Boulevard from Balboa Street.

MORE NEWS: Stockton Woman Fatally Shot Over The Weekend

This story will be updated.