PLAISTOW — Three adults have died at 5 Center Circle, Town Manager Sean Fitzgerald confirmed.
A fourth adult was taken to a hospital for treatment.
It's believed to be carbon monoxide poisoning.
The call came at 10 a.m., according to Deputy police Chief Kathleen Jones.
The state fire marshal is on the scene, as are Plaistow police and fire personnel.
An announcement is expected soon with details.
"Obviously, we are very heartbroken and saddened by this tragedy," Fitzgerald said. "It's a very tight-knit neighborhood. It will be a tough loss for the town."