FREMONT (CBS SF) — A vegetation fire in Fremont shut down a major road in the city Tuesday, authorities said.

The fire began around noon off of State Road 84/Niles Canyon Road blocked a section of the road between Pleasanton Sunol Road and Fremont city limits.

Fremont Fire, Alameda County Fire, and Cal Fire units were on the scene in “extremely steep and rocky terrain,” according to a tweet from Fremont Fire Department.

As of 1:30 p.m. firefighters were mopping up, extinguishing hot spots and improving containment lines, according to Fremont Fire Dept.

Motorists were advised to avoid travel via Niles Canyon Rd for the remainder of the afternoon.

The amount of acreage involved was not immediately available.