No one was injured, though dozens were temporarily forced out of their apartments.

As firefighters fought the blaze, the Fire Department arranged for Metro Transit buses to come to the scene to keep about 30 tenants warm after they fled the Lincoln Estates Apartments at 2710 9th Lane.

A staff member for Lincoln Estates said management will pay for residents from the building’s 30 to 35 units to stay in motels for two days during repairs of utilities and building mechanicals.

Seventy to 80 people who live in the three-story building have been temporarily displaced, said building and fire officials.

“Most people were out, [but] there were a few people that were actually in there yet,” Anoka Fire Chief Charlie Thompson said of the scene firefighters found when they arrived. “They were able to get out very quickly,” after emergency personnel arrived, he said.

The discovery of the blaze — midmorning rather than in the middle of the night — helped avert tragedy, the fire chief said. The 911 call came in at 9:59 a.m., when a caller reported smoke on the first floor.

The fire began in a utility room, then climbed two stories up a 2-foot-wide vent, Thompson said. Fire also spread inside the walls.

Apartment buildings and townhouse complexes with a shared attic and roof pose special risks because the fire can spread quickly, he said.

“This one was a hard one; there were concrete walls following the vent all the way up,” Thompson said. “So we had to cut a hole in the concrete roof and make sure everything was extinguished — the trusses and the rafters and each floor.”

There were no sprinklers in the building, which Thompson estimated was built in the late 1950s, before sprinklers were required.

It wasn’t immediately known if smoke detectors went off.

Thompson said the building’s utilities are out of service, so that residents would not be able to return soon. He said there was significant fire damage to the utility room and smoke and water damage throughout the building.

Smoke damage could have been worse, he said, but many apartment doors had remained shut.

Ramsey and Andover fire crews assisted Anoka-Champlin crews at the fire, which took two hours to bring under control.