Prompt action by firefighters Wednesday evening saved a former mill building that now houses two food distribution companies, according to fire Chief Brian Moriarty.

One firefighter suffered minor injuries but is expected to fully recover, the chief said. No civilians were hurt.

A working fire in the building at 85 Manchester St. was reported by telephone at 6 p.m. Engine 7, based at the nearby Park Street firehouse, was the first to respond. The second alarm brought all Lawrence engines to the scene, plus crews from Salem, New Hampshire, and Andover.

Ladder 4 sprayed water on the roof while other engines attacked the fire from different positions.

Engine 5, connected to a hydrant on Broadway, pumped water to the other trucks through about 1,000 feet of 6-inch hose.

Damage was contained to the roof, Moriarty said. The roof, with an old-fashioned sawtooth style, proved to be a challenge, he added.

The thick roof, measuring at least 6 inches and constructed of planks and rubber, was “a very tough area,” Moriarty said.

A sprinkler head in the building helped bring the fire under control, he said. Firefighters began leaving the scene by 8 p.m.

The two food distribution companies are Bulk Services and Dragon Joy. City health inspectors were assessing the building Wednesday night to determine whether employees can report for work Thursday, Deputy Chief John McInnis said.

The employees of the nearby Microsemi Corp., 6 Lake St., were evacuated. Police blocked Broadway between Park and Manchester streets while firefighters suppressed the blaze.