NEW MILFORD, Conn. (AP) – An explosion at an outdoor party early Sunday killed a 22-year-old man and injured seven others, police said.

Sean Caselli of New Milford died after something exploded in or near one of several barrels in which fires had been set to keep partygoers warm outside a home on Aspetuck Road, said New Milford Police Captain Michael Mrazik.

Witnesses told police they saw someone put what appeared to be a quarter-keg of beer into one of the burning barrels just after 3 a.m.

Seven people suffered non-life-threatening injuries, including burns and shrapnel wounds, police said.

Over 50 people attended the party, which was an annual event, neighbors said.

“This is a certain tragedy,” said Police Chief Colin McCormack. “However, nothing I have been apprised of to this point in this investigation, which I caution is at the very early states, indicates a deliberate act on anyone’s part.

Robert Greco, who lives in the area, went to the scene after hearing the explosion. “It was an unbelievable explosion,” Greco told the News-Times of Danbury. “It rattled the street.”