Reports of suspicious man prompts lockdown at schools in Mill Valley

Police activity in Mill Valley prompted a lockdown at two schools Monday afternoon after reports of a suspicious man in the area.

Police Chief Al Piombo said at least three people called 911 to report a man behind Tamalpais High School on Homestead Boulevard. They said he was dressed in all black and wearing a ski mask. One caller said they thought the man had a gun.

As a precaution, the high school and a nearby middle school were placed on lockdown. Residents in the area were asked to shelter in place. 

Officers searched every room at Tamalpais High School and found nothing.

At around 4:01 p.m. the lockdown and shelter in place were lifted and students were released from school as usual. 

Officials said all students were safe. 

Officers are searching for a white vehicle that was in the area and possibly linked to the incident.