SANFORD — Three boys have been charged with felony arson in connection with the massive fire that destroyed the Stenton Trust Mill building in Sanford on Friday night.

The boys – two 13-year-olds and a 12-year-old – were arrested Sunday night and Monday morning and taken to the Long Creek Youth Development Center in South Portland, the state Fire Marshal’s Office said.

All three appeared Monday morning in Biddeford District Court and denied responsibility for one charge each of felony arson, court records show.

Because the charges are felonies, the boys are identified in court documents. The Press Herald is withholding the names of the children until officials release more details about how the fire started.

State Fire Marshal Joseph Thomas declined to give specifics about what investigators believe happened, but he said the use of a drone allowed them to identify a third-floor area where they believe the fire began.

“We could see some of the burn patterns that we would characteristically look for doing an investigation inside the building,” Thomas said at a brief news conference next to the mill complex.

All three boys are from Sanford, according to court paperwork. The Press Herald tried to contact their parents, but they could not be reached Monday. All three boys are due back in court on July 27.

“The juvenile fire-setter problem within the state of Maine, as well as the country, is still quite substantial,” Sanford Fire Chief Steve Benotti said. “It comes from a number of things, a fascination with fire and a host of other things. I think in this case I think these people thought they were used to doing some things and got away from them. It’s still quite rampant throughout the state.”

Friday night’s fire was the largest mill fire Sanford firefighters have ever battled. It rivaled a 1984 New Year’s Eve fire in Sanford that destroyed several businesses and apartment buildings on Washington Street.

According to the state fire marshal’s 2015 annual report, the most recent year for which statistics are available, investigators cataloged 312 instances of juveniles setting fires.

About a third of them – 102 incidents – were building fires that caused nearly $3.68 million in damages statewide, or most of the $3.9 million in statewide property damage caused when children set fires.

On average between 2010 and 2015, the most recent years for which statistics were available, juveniles set 239 fires annually.

Thomas and Benotti said the boys were lucky to get out of the building because the fire spread so quickly. They did not use any accelerant such as gasoline, Thomas said.

Investigators used aerial footage from drones and footage from nearby security cameras to analyze the path of the fire and determine where it was ignited, Thomas said.

Fire officials also said that two men who had been staying in the building and were thought to be missing were located Monday morning in Portland.

Investigators have been unable to enter the building because damage caused by the fire has made it unstable. Excavation equipment is being brought to the site to help stabilize the building, and a fence is expected to be erected Tuesday to keep people away from the scene.

Investigators also have been hampered by hot spots that have continued to flare up since the fire ripped through the back building of the complex at 13 River St.

The complex includes two five-story brick and concrete buildings and a one-story connecting structure. The front building, which faces River Street, sustained minor damage from the fire. More than 100 firefighters from 20 communities helped battle the blaze, which attracted hundreds of people who recorded the fire on their phones and shared dramatic images on social media.

Attention has now turned to cleaning up and likely tearing down the mill complex.

Sanford City Manager Steven Buck said the city has received an early estimate of $500,000 to tear down and remove both five-story mill towers. Buck said that figure does not include environmental costs, which could be substantial, given the buildings’ age and the likelihood they contain hazardous materials such as asbestos or lead paint.

Buck also said the city is working to determine who owns the property. City tax records show that the property and surrounding acreage is owned by Jonathan Morse of Gateway Properties LLC. Gateway was recently registered as being based in Maine, but Sanford tax records connect the company to Reno, Nevada.

A message left for Morse was not returned Monday, but Buck said Morse has communicated with the city and denies that he owns the building. Banks and other institutions once connected to the property are now claiming no connection to it.

“We’re doing research on it,” Buck said. “They’re all saying not us, not us.”

Buck said city taxes have gone unpaid for years and that municipal officials soon will have to decide how to proceed. Ideally, he said, both towers would be demolished.

“The owners of register have had limited contact with the city,” Benotti said. “These buildings have been a nuisance to the city for quite some time.”

Matt Byrne can be contacted at 791-6303 or at:

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