A 3-year-old Caribou boy started the fire that killed him, his mother and two siblings Thursday, the state Fire Marshal’s Office says.

Trenton Delisle, who would have turned 4 next week, is believed to have started the fire in the living room of the mobile home where he lived with his family, an aunt and two cousins.

Also killed, besides Trenton, were Norma Skidgel, 28, and Mason and Madison Delisle, 2-year-old twins.

“Indications are that there was a previous history (of fire-starting),” state Fire Marshal Joe Thomas said.

Three of the victims died of smoke inhalation, according to the Maine State Medical Examiner’s Office, which had yet to complete an examination of the fourth victim Friday evening.

There were no working smoke detectors in the home – the only one found by investigators had its battery removed.

Although construction regulations require that mobile homes have two exits, Thomas said the back door was blocked by a piece of foam, likely there as insulation.

Mobile home fires can be particularly dangerous because of the construction methods and materials used, which often have composite or particle-board paneling attached to interior walls by combustible adhesives.

The blaze was the second fire that Trenton started Thursday morning, according to investigators. He had earlier set a Bible on fire in the kitchen’s oven. Amy Bouchard, Skidgel’s sister, put out that fire before she left the house to walk one of her sons to a bus stop. Bouchard’s other son was not home at the time of the fire.

“Juvenile fire starters are a huge problem in Maine and there are resources available throughout the state to counsel, educate and treat children fascinated by fire,” Thomas said. “Parents and guardians can seek help by calling their local fire department or the State Fire Marshal’s Office in Augusta.”

In the 10-year period ending in 2011, 2,531 fires were started by juveniles, resulting in 14 deaths and 115 injuries, and causing about $40 million in property damage, according to a study conducted by the State Fire Marshal’s Office.

Last year, 276 fires were started by juveniles, Thomas said. No figures were available for 2014.

Skidgel was pronounced dead at the scene. Her children were rushed to Cary Medical Center, where they were pronounced dead. All four bodies were found in a back bedroom.

Bouchard was treated for smoke inhalation after she tried to enter the mobile home. Yvonne Skidgel, Norma Skidgel’s mother, declined to comment Thursday.

The fire at the Westgate Mobile Home Park was reported around 7 a.m. Thursday. The mobile home park is located about a mile southwest of Loring Commerce Centre, on the town line with Limestone. From aerial photos, the park appears to contain about 18 mobile homes.

The owner of the mobile home park is Maggie Ventures, LLC, according to Caribou city records. The company is located in Las Vegas. Lawrence Phillips, the company’s manager, could not be reached for comment. The property was purchased by Maggie Ventures in October 2013, according to Caribou city records.

The fire is the deadliest in Caribou in “modern times,” Thomas said. Of the 25 people killed in Maine by fires this year, 11 deaths occurred in November, said Stephen McCausland, spokesman for the Maine Department of Public Safety.

Six young people died Nov. 1 in a blaze on Portland’s Noyes Street. Investigators are still working to determine the cause of that fire. On Wednesday, an elderly St. Francis man was killed after he tried to start his wood stove with gasoline.

Matt Byrne can be reached at 791-6303, or at:

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