A four-alarm fire broke out at 877 Beacon St. at about 1:25 a.m. Sunday morning, injuring four firefighters and temporarily displacing more than 40 residents from their apartments.

Boston and Brookline fire departments responded to the scene. The fire originated on the first floor of the office building and the fire went up the walls, rising through the roof, said Steve MacDonald, spokesman for the Boston Fire Department.

The fire was contained to the building and did not spread to surrounding apartments due to a protective firewall. However, residents in the surrounding apartments in 875 and 879 Beacon St. were evacuated, MacDonald said.

Four firefighters were treated for injuries. Boston Emergency Medical Services treated two firefighters on the scene: one for a shoulder injury and another for an ankle injury. The other two were transported to local hospitals for treatment for burns and have since been released, MacDonald said. There were no reported resident injuries.

Residents from the surrounding apartment buildings were placed on buses provided by the Massachusetts Bay Transportation Authority out of protocol. Many of the residents affected by the fire were Northeastern University students, MacDonald said.

“When people are displaced, many run off to their friends and family members to stay, so we can’t be sure of how many people total were displaced other than who we see on the buses,” he said.

Residents were allowed to return to their apartments at about 4:30 a.m., MacDonald said.

Witnesses reported seeing a lot of smoke as they watched the scene from the corner of Beacon Street and Park Drive, not far from Boston University’s South Campus.

Approximately 80 firefighters, 70 from Boston units and 10 from Brookline, remained on scene to monitor and investigate the fire, MacDonald said. The units left the scene around noon.

Most of the building was burned and parts of the roof caved in, MacDonald said. The fire resulted in an estimated $3 million in damages.

Rachel Riley contributed to the reporting of this story.