SAN FRANCISCO (KRON) -- Three southbound lanes of US-101 were blocked after a crash on Wednesday afternoon, according to a 511 alert. An overturned box truck laid in the road as a result of the collision. All lanes have since reopened. The crash happened before 4:30 p.m. on the highway south of Cesar Chavez Street. There were three vehicles involved, and people involved suffered just minor injuries. Drivers are told to avoid the area and expect delays.