MARIN COUNTY (KRON) – Only one lane is open on southbound US-101 in Marin County as of 7:30 a.m. Tuesday, California Highway Patrol told KRON4.

Lanes 1-4 were closed due to a vehicle collision near the Seminary Drive exit in Mill Valley. As of 9:16 a.m. all lanes have reopened.

This is a developing story. Check back for updates.