Dozens of explosions, apparently triggered by a natural gas pipeline rupture, rocked three communities near Boston on Thursday, killing at least one person, injuring 12 and prompting the evacuation of hundreds, officials said.
The blasts left scores of homes and other buildings demolished or engulfed in flames as firefighters from some 50 departments scurried for hours from one blaze to another and utility crews rushed to shut off gas and electricity in the area to prevent further ignitions.
Police drove up and down streets with bull horns telling residents to vacate their homes immediately.
Fire investigators suspected "over-pressurization of a gas main" belonging to Columbia Gas of Massachusetts led to the series of explosions and fires, Andover Fire Chief Michael Mansfield said at a news conference.
Columbia Gas, a unit of NiSource, had announced earlier in the day that it would be upgrading gas lines in neighborhoods across the state, including the area where the explosions occurred. But it was not immediately known whether any work was being done in those communities at the time.
"Columbia Gas is investigating what happened on its system today," NiSource spokesman Ken Stammen said.
The U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA) said it was dispatching a team to support the state's emergency response efforts.
The former head of that agency, Brigham McCown, called the series of gas explosions "unprecedented, at least in recent memory."
"I can't think of a series of natural gas-related incidents like this," McCown, who led PHMSA under then-President George W. Bush, told Reuters by telephone. "We have had similar issues on a much smaller scale."
He said the National Transportation Safety Board was also sending a team headed by its chairman, Robert Sumwalt, to investigate the disaster.
Live TV images showed firefighters battling blazes in the former mill towns of Lawrence, Andover and North Andover, about 25 miles (40 km) north of the Massachusetts capital.
The streets were darkened after nightfall as power was cut off to the area as a precaution.