Fire departments from several towns responded to a two-story home on Brewer Lake Road in Orrington around 2:30 a.m. on Saturday.
Orrington Fire Chief Scott Stewart told us the building was fully involved upon arrival.
In a statement, the State's Fire Marshal's Office says two of the home's five occupants were killed in the blaze.
They identified one of the victims as 55-year-old Shelly Lynn Murphy.
They said the other victim is a middle-aged man, but relatives are still being notified.
The three who made it out suffered minor burns and smoke inhalation.
"All of them refused treatment and transport to the hospital," Stewart said. "The Red Cross is taking care of those folks immediate needs."
The State's Fire Marshal's Office believes the fire started in a first-floor bedroom but the cause is still under investigation.
We will update this story as more information becomes available.