YARMOUTH — An explosion at a duplex subdivision off North Road on Tuesday killed one man, injured four people, leveled a home and damaged more than a dozen other buildings.

Peter Corey, 66, was killed, said his brother, Walter Corey, who owns the property at 50 Gables Drive where the blast occurred at 6:17 a.m.

The cause of the explosion was undetermined, but investigators were eyeing propane as a possible culprit, said Sgt. Ken Grimes of the State Fire Marshal’s Office.

Four people who suffered minor injuries were treated and released, including a firefighter who suffered from exhaustion, Yarmouth Police Chief Michael Morrill said.

“It’s hard to believe,” Morrill said, referring to the number of injuries as he stood on blast debris in a neighbor’s yard, more than a hundred yards away from the blast scene, where pieces of yellow insulation were still floating in the air.  

The explosion on Gables Drive appeared to be fueled by propane gas, although Morrill said the cause is still under investigation.

“Police are talking with all the residents to hear what they saw, heard and smelled,” he said at a press briefing at about 8 a.m.

Robert and Rosemary MacKay, residents of the adjoining unit, 52 Gables Drive, were injured, as was Mary Hallsey, a resident of an adjacent building, according to a news release from the Department of Public Safety.

The explosion took place on a quiet, dead-end street lined with 14 condominium units. The subdivision, which is called Gables North, was built in the mid 1980s. Most of the residents are elderly, Yarmouth Fire Chief Michael Robitaille said.

At least four units will have to be rebuilt, said Jeff Martin, owner of Foreside Real Estate Management, the company that manages the properties. The count could rise to as high as eight, he said.

The blast occurred without warning, said neighbor Amory Houghton, who lives at 34 Gables Drive.

Houghton had been walking toward the end of his driveway to get the morning paper when he paused to clean out his car. It was a decision that might have saved his life, he said.

“All of a sudden there was this horrendous explosion and a pall of smoke,” Houghton said.

He ran into the street to see what had happened. The roof of a nearby home was ripped off. The house at 50 Gables Drive was “down to the sticks,” he said. Houghton ran indoors to call 911, but emergency responders were already arriving.

“It was an extremely quick response,” he said.

Firefighters at first treated the scene as if it were a mass-casualty situation, and immediately dispatched first responders from Cumberland, Falmouth, Gray, North Yarmouth, Portland, Topsham and Westbrook to assist, Robitaille said.

The swath of damage extended as far as 200 yards in all directions, and the sounds and vibrations from the blast were felt as far away as Portland. Yarmouth Police Lt. Dean Perry was in Falmouth when he heard and felt the explosion rattle the earth below his feet. Seconds later, he was dispatched to the scene.

Fiberglass insulation landed about a mile away on East Main Street. Two blocks away, the Yarmouth Fire Station sustained minor damage and a deputy was knocked down by the blast wave. About 100 yards away, Robert W. Boyd Amvets Post 2, where a town election was scheduled to be held throughout the day Tuesday, suffered cracked plaster and blown-out ceiling tiles. About a block away in the opposite direction, pipe joints came apart in the town garage.

Elizabeth Dobson, who lives on North Road, said she felt the blast at her house.

“I saw flashes and a ball of light and then a boom,” she said, noting that it blew open dresser drawers and doors. “It looked like someone had come through to steal stuff.”

Closer, on a street parallel to Gables Drive, several houses were damaged, including Maryann Gordon’s two-story house.

Gordon, who lives with her husband at 67 Balsam Drive, gave a tour of her blast-damaged house. Windows on all sides were shattered or blown out of their frames. Gordon’s house is less than 75 yards from the blast site, separated by a stand of conifer trees. She was lying in bed when it happened.

“It was concussive,” Gordon said of the shock wave.

Even windows on the far side of the house were blown inward from the blast’s repercussions.

Two hours after the explosion, Morrill stood on debris in a neighbor’s yard, more than 100 yards from the blast scene, and remarked on the low number of casualties.

“It’s hard to believe,” he said, as pieces of white insulation continued to float in the air like drifting dandelion seeds.

Several hours after the blast, investigators were still combing through the debris. Residents on the street were kept out of their homes while engineers surveyed each structure for stability. Gables Road was closed throughout the day.

Grimes couldn’t estimate how long the investigation would take, but it would include interviewing neighbors to see if anyone smelled anything prior to the blast or if any recent maintenance had been done at Corey’s home.

Propane provides heat and hot water for the units. Houghton said the units also have propane fireplaces and cook stoves.

Corey’s body was found at the blast site, but Grimes wouldn’t say exactly where.

Neighbors knew little about Peter Corey, but the neighborhood association was concerned about him, Houghton said. Corey was handicapped and deaf, so communicating with him was difficult. Members of the neighborhood association wondered if Corey was able to fully care for himself, Houghton said. Walter Corey declined to answer a reporter’s questions when reached by phone Tuesday morning, but he confirmed that his brother had been killed.

“I’m devastated,” he said. “He was my only brother.”