SANFORD — Authorities believe a fire on Saturday, July 6, that destroyed a house on Montreal Street and damaged a duplex is a case of arson.

The Sanford Fire Department received a report of a fire on the porch at 26 Montreal St. at 4:26 a.m. By the time firefighters arrived at the scene moments later, the home had become engulfed and the flames had jumped to the duplex next door at 24 Montreal St., according to Fire Chief Steven Benotti.

“The fire spread pretty quickly,” Benotti said Monday.

No one was injured in the blaze, but eight people have been displaced — three adults who lived at the single-family residence at 26 Montreal St. and three roommates and a couple who, respectively, lived on the first and second floors next door, according to Benotti. The American Red Cross reported to the scene and assisted these individuals, he added.

Residents in neighboring homes were evacuated as a precaution, according to a post on the Sanford Police Department’s Facebook Page.

The local police department and the offices of the city and state fire marshals are investigating the blaze, “which is considered an act of arson at this time,” according to the post on Facebook.

Currently, authorities are seeking two individuals of interest who were seen outside of 26 Montreal St. just minutes before the fire was reported. The two individuals can be seen on some black-and-white video footage that the Sanford Police Department has posted on its Facebook Page.

Anyone who might be able to identify the individuals, or has other information about the fire, is urged to contact Det. Colleen Adams at (207) 324-9170, ext. 226. Anonymous tips also may be left on the Office of the State Fire Marshal Arson Hot Line at 1-888-870-6162.

Benotti said that the structure where the fire originated is a “total loss.”

“It’ll have to be torn down,” he added.

The duplex next door, however, is fixable, according to Benotti. The siding on one side of the structure is burnt, and some windows were broken too. The building also sustained some water damage from the firefighters’ efforts to suppress the flames.

Benotti said firefighters had the scene under control in about 35 or 40 minutes, with the main body of the fire at 26 Montreal St. knocked down in roughly 20 minutes.

Firefighters from Acton, Alfred, North Berwick, Wells, Lebanon, and Goodwin Mills all assisted at the scene. Firefighters from Arundel, Kennebunk and Saco, as well as personnel from the Wells Emergency Management Service, provided station coverage.