(CNN) -- A powerful explosion tore through a duplex in Brentwood, New Hampshire, Monday afternoon, after a man shot and killed a police officer who responded to a domestic dispute there, authorities said.
The blast was captured live on air by CNN affiliate WCVB-TV.
Officer Steve Arkell was fatally shot by Michael Nolan, 47, according to New Hampshire Attorney General Joseph Foster. A second officer responded to the scene but was driven away by gunfire, Foster said.
"Other officers arrived and a short time later the home was engulfed in flames and later exploded," he said. "It's believed Mr. Nolan was killed by the fire or the explosion."
The incident is being investigated by the state and federal authorities, according to Foster.
The 48-year-old Arkell was married and the father of two teenage girls, affiliate WMUR reported.
Gov. Maggie Hassan ordered that flags in the state be flown at half-staff in his honor.
"I join all Granite Staters in mourning the loss of Brentwood police officer Steve Arkell, who died tonight doing his job, protecting his community," she said.
Brentwood is a town of about 4,200, located 50 miles north of Boston.