The investigation continues into an April fire in Randolph that injured one and left four homeless.

Andrew James St. Amand, 34, had been a suspect in the April 9 fire inside the apartment building at 23 Windsor St.

The building burned later that day, and witnesses told fire investigators they heard St. Amand threatening to burn the building down after allegedly having a fight with his girlfriend. St. Amand was indicted Oct. 7 on charges of domestic-violence assault and violating conditions of release, but not arson.

On Monday, Sgt. Kenneth Grimes, an investigator with the fire marshal’s office, left open the possibility of additional suspects.

“I can tell you we have a person in mind we’re looking at,” he said Monday. “We’ve met with the district attorney and we discussed things we might be able to do in this case.”

Grimes declined further comment, referring questions to the office of District Attorney Evert Fowle, who was away at a conference Monday.

At the time of the fire, the building — which since has been razed — was owned by Gov. Paul LePage’s spokesman, Dan Demeritt, of Sidney.

Demeritt resigned a week later after the Kennebec Journal reported he faced foreclosure on the Randolph building and four others he managed as a landlord.

The Randolph building was part of a three-address parcel for which Demeritt was facing foreclosure.

Demeritt owed $251,192 to Bank of Maine for allegedly failing to pay principal, interest, late charges, taxes, insurance advances and attorney fees. The properties were valued for tax purposes at $378,400.

St. Amand stands charged with domestic-violence assault and violation of condition of release, both felonies, and has been held at the county jail since. Investigators said St. Amand sustained minor injuries, possibly related to the domestic violence incident. Witnesses said he escaped the fire by climbing out a second-floor window and down a tree.