SAN FRANCISCO (KRON) -- A jackknifed big rig is blocking multiple lanes Thursday morning on the Bay Bridge in the eastbound direction in San Francisco, east of the First Street onramp, according to California Highway Patrol. The four left lanes of Interstate 80 were blocked after the crash at 5:10 a.m. As of 8:30 a.m., the three left lanes are blocked, with the two right lanes open. The estimated time to clear all lanes is between 9 a.m. and 9:30 a.m. Bomb cyclone and atmospheric river to hit Bay Area: Latest updates According to the CHP incident report, the big rig lost control before jackknifing on the interstate. No other vehicles were involved in the crash. The big rig sustained major front end damage. A big rig jackknifed on eastbound I-80 Nov. 21, 2024. (Photo: CHP)A big rig jackknifed on eastbound I-80 Nov. 21, 2024. (Photo: Caltrans) The big rig driver reportedly sustained injuries in the incident. The severity of the driver’s injuries and their current condition is unknown. The San Francisco Municipal Transportation Agency (SFMTA) said heavy traffic due to the crash is impacting Muni service in the downtown area around Mission and First streets. "The 14, 14R, & 25 routes are most heavily impacted at this time," SFMTA announced just before 8 a.m. This is a developing story. Check back for updates.