NEW MILFORD — The fire that damaged four units in the Harrybrooke Park Condominiums early Tuesday was caused by improperly disposed of charcoal grill contents, fire officials said.

That’s what Deputy Fire Marshal Kevin Reynolds said Tuesday afternoon, hours after the blaze was knocked down.

The fire broke out at 13 Harrybrooke Park Condominiums around 4:30 a.m. No one was injured, said Mayor Pete Bass.

Smoke detectors alerted occupants of the units and police quickly evacuated the remainder of the building.

Water Witch Hose Company No. 2’s first officer on the scene was met by heavy smoke pushing from the attic of the entire building and fire consuming a portion of the rear wall spanning three floors.

A second alarm was sounded bringing help from Northville, Gaylordsville and Brookfield to the scene. The fire was under control by 7 a.m., fire officials said.

Later, Danbury provided an engine and crew to help with overhaul, their air supply truck ready to refill air packs at the location.

The American Red Cross was on the scene to help those displaced. Bass said the town’s services team will also be providing assistance.

Fire command was terminated at 8:20 a.m. — but firefighters returned to the scene four hours later after a caller reported the fire rekindled.

A firefighter on scene reported a “small area of fire in the back of the building” at 12:26 p.m.

“It was really nothing — just a very small fire that started back up,” Reynolds said.