LAWRENCE, Mass. • A series of gas explosions left at least four people injured and ignited fires in at least 39 homes in three communities north of Boston on Thursday, forcing entire neighborhoods to evacuate as crews scrambled to fight fires and turn off gas and electric lines to prevent further damage.

Massachusetts State Police urged all residents with homes serviced by Columbia Gas in Lawrence, Andover and North Andover to evacuate Thursday afternoon, snarling traffic and causing widespread confusion as residents and local officials struggled to understand what was happening.

A man whose neighborhood was among dozens that erupted in fire says he ran into his basement to find that the room was glowing. Lawrence resident Ra Nam says he was in his yard when the smoke detector in his basement went off around 4:30 p.m. EDT Thursday.

When he ran downstairs and saw the boiler on fire, he quickly grabbed a fire extinguisher and put it out. Minutes later, Nam said he heard a loud boom from his neighbor’s house and the ground shook. Nam said a woman and two kids had made it out of the house but the basement was on fire.

Lawrence resident Bruce Razin was among the evacuees standing outside the Colonial Heights neighborhood near the city’s high school trying to decide what to do next late Thursday.

Officials had cut power in the area and the streets were pitch black, save for emergency vehicle lights. Razin said he arrived just as residents were being evacuated, and immediately saw the house two doors down was leveled from an explosion.

“I couldn’t imagine if that was my house,” said Razin, who purchased his home nearly two years ago. “It’s total destruction. I’d be completely devastated.”

Lawrence General Hospital said it was treating four victims with injuries related to the fires but did not provide details about their conditions.

The Massachusetts Emergency Management Agency blamed the fires on gas lines that had become over-pressurized, but officials who responded to the area were still investigating the cause.

In this image take from video provided by WCVB in Boston, flames consume the roof of a home Thursday in Lawrence, Mass.

the associated press