Three Sanford boys are charged with arson for a fire that destroyed the Stenton Trust Mill in Sanford, said the State Fire Marshal’s Office.

Gord Horne/Thinkstock

A 12-year-old boy and two 13-year-old boys are at the Long Creek juvenile detention facility in South Portland. They were arrested Sunday. Once paperwork is filed at the Sanford District Court, their first appearance will be scheduled, said Stephen McCausland, Public Safety Spokesman.

Investigators tracked down the two missing men following the fire. They have been located safe in Portland Monday morning, said the Fire Marshal’s Office.

The building has been stabilized with excavation equipment. Fire Marshals will be assisted today by investigators from the Federal bureau of ATF, along with State Police, Sanford Police and the Sanford Fire Department.

An update on the investigation is scheduled for 1 p.m. Monday at the Fire Marshal's mobile command post. Fire Marshals and Sanford Fire Officials will hold a news conference.