CORONA (CBSLA) — A fast-spreading brush fire that officials said was moving at a “critical rate” broke out in Corona on Monday afternoon.

The Sierra Fire was reported at 4:19 p.m. and continued burning after 5:30 p.m. It originated at La Sierra Avenue and Cajalco Road, which have been temporarily closed as crews continued to battle the flames.

Cal Fire/Riverside County Fire Department was in unified command with the Corona Fire Department. At last check, 172 firefighters were assigned to the fire.

Around 4:54 p.m., Cal Fire reported the fire was approximately 30-40 acres. It spread to 60 acres with 0% containment at about 5:24 p.m. About 10 minutes later, the fire spread to 100 acres and was 5% contained.

At 6:12, officials said the rate of spread stopped and the fire was 25% contained at 110 acres. At 9:55 p.m., officials said the fire was 80% contained to 97 acres. The change in acreage was due to better mapping, according to authorities.

Cal Fire said “resources will remain on scene throughout the night and into tomorrow for overhaul.”