An investigation by the State Fire Marshal’s Office into the cause of the blaze that destroyed part of the Stenton Trust Mill complex in Sanford on Friday night was delayed for a second day Sunday.

State Fire Marshal Joseph Thomas said that his office is trying to obtain equipment to take down unsafe parts of the building at the complex before sending investigators inside. He said so far efforts to find the equipment have not succeeded.

“We have been working through the weekend to find heavy equipment to be able to dismantle the building because of the precarious conditions. We don’t want to put anyone in there until” it is safe, Thomas said Sunday.

Thomas said it would be Monday at the earliest before investigators could enter the building. Investigators have also been hampered by hot spots that have continued to flare up since the fire ripped through the back building at the complex at 13 River St.

The complex includes two five-story brick and concrete buildings and a connecting structure. The front building, which faces River Street, sustained minor damage from the fire.

Firefighters continued to hose down the smoking remains Sunday.

“We spent most of the day Sunday chasing hot spots,” said Capt. Dwight Emmons of the Sanford Fire Department.

Emmons said he expects that demolition equipment will be brought in at some point to knock down sections of the mill building that are considered unsafe.

“Right now, it’s just not safe. There is a fear of collapse,” Emmons said Sunday evening.

Emmons said Sanford police have been assigned to keep an around-the-clock eye on the building to make sure that no one tries to get inside.

City Manager Steven Buck said Saturday that the mill property is being treated as a possible crime scene. Though the cause has not been officially made public, investigators have not ruled out arson. There was no official word Sunday evening on whether anyone had been arrested.

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

Matthew O’Shaughnessy, a spokesman for the federal Bureau of Alcohol, Tobacco, Firearms and Explosives in Boston, confirmed Sunday that special agents from the ATF’s Portland office have been assisting the State Fire Marshal’s Office with its investigation.

O’Shaughnessy said he could not comment on the status of the investigation because the fire marshal’s office is in charge of the investigation. Also investigating the cause of the blaze are Sanford police and the Sanford Fire Department.

Steve McCausland, spokesman for the State Fire Marshal’s Office, said more information about the cause of the fire should become available Monday.

“I don’t have anything more definitive to add tonight,” McCausland said Sunday night.

Sanford police asked on their Facebook page that anyone with information about the fire contact them at 324-3644 ext. 170. Police also asked people not to spread rumors about the incident.

One hundred firefighters from 20 departments battled the blaze Friday night. No one was injured, officials said.

The building’s last owner of record was Jonathan Morse of Gateways Properties LLC, who left the area about a decade ago and now lives in Reno, Nevada, according to Sanford tax records. The buildings had been condemned by the city’s inspection department.

In a telephone interview Sunday evening, Morse confirmed that he lives in Reno but denied that he owns the Stenton Trust Mill property. Morse said he does not know who owns the property now, adding that the matter is “complicated.”

Paula Simpson, Sanford’s tax collector and treasurer, said in an email Sunday that the mill ownership is “pretty complicated” and that “the city will need to release a statement.”

Morse said the city of Sanford shares some of the blame in the mill complex’s decline.

“It disappoints me because at one point it had such great potential to beautify that area and give great significance to the history of the city,” he said. “But the people who controlled its future are in city government.”

Deputy Mayor Maura Herlihy said the mill complex was considered an important piece of Sanford’s development plans for its vacant mill buildings, but she said interested developers would drop out when it became clear that the back building was in terrible shape.

A redevelopment company, Boston Commons Investments LLC, paid $210,000 for the property in a foreclosure auction in 2009 before backing out of the deal, according to Herlihy.

Herlihy said the complex, which has a history of attracting vandals and vagrants, has been the scene of several minor fires in the past.

Beth Quimby can be contacted at 791-6363 or at:

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Dennis Hoey can be contacted at 791-6365 or at:

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