Firefighters were battling a 3-alarm house fire in Brookline on Thursday, according to local departments.

The blaze was reported at 90 Sargent Road in Brookline.

After about two hours, “most of the heavy fire is knocked down,” Brookline Fire posted at 12:30 p.m.

“Firefighters remain on scene for overhaul and checking for extension,” the fire department added. “Strong work by group 4 and a huge thank you to Cambridge, Boston and Newton for their assistance and coverage.”

Police were telling people to avoid the area.

“Traffic Advisory: Brookline Fire Department dealing with structure fire in Warren/ Walnut St area: please avoid area if possible,” Brookline Police posted.