Power surge sparks thousands of outages in Waltham, did it also spark a fire?

Firefighters responded Monday morning to a fire in Waltham, Massachusetts, where thousands were without power, and investigators are working to determine if a power surge is to blame.

The sound of fire alarms filled a Waltham neighborhood when flames erupted shortly before 9 a.m. in a multi-family home on School Avenue moments after a sudden surge of power.

The fire is now out, and nobody was hurt, but some in town worry this could happen again if there's another power surge.

“There was a loud pop that was inside my house, and the TV went out, the lights went out. The phone went out,” said Jackie Thomas, who lost her power Monday.

Investigators are still trying to figure out if the electrical surge is to blame for the smoky fire. Six people live in the building, but only one -- a teenager -- was at home when it started and was able to get out safely.

Eversource said they responded to the power outage in Waltham just before 8:30 a.m. "and worked as quickly as safely possible and restored power to all affected customers within one hour." They said they are still working to determine the cause of the outage.

In all, Eversource says about 6,000 customers lost their electricity because of what happened.

"The bottom line today is making sure we do have a significant number of people out here, taking a look at all of the infrastructure to make sure it is safe," Chris McKinnon, with Eversource, said. "We have extra crews on scene, we have electricians that are going door to door right now to inspect their equipment inside their own home. On the other end of things, we're also checking all of our electric infrastructure to see if we can determine and get tot he bottom of exactly what caused this earlier this morning."

Besides the house, a small shed in neighborhood caught fire while firefighters responded to dozens of calls starting around 8:30 a.m.

”We had 40 calls within a very short amount of time so we’ve been trying to clear all those calls. Mostly surges, burnt out power strips, and whatnot," Fire Chief Andrew Mullin said.

It’s not the first surge Waltham has experienced in recent months. Last fall, an Upper Main Street neighborhood went through the same sort of thing.

”Eversource was good last time. They were very good. But we have to get to the bottom of what’s happening here because this is the second time we’ve had it,” Mayor Jeanette McCarthy said.

”What we need is a prevention plan from Eversource to making sure we actually understand how this is not going to happen again,” City Councilor Jonathan Paz said.

McKinnon said Eversource crews worked with the city's wire inspector team, fire department and private electricians to go to the homes of any customers who reported issues or concerns following Monday morning's power outage and voltage surge.

Crews inspected the electric equipment both inside and outside of those homes to ensure customers are safe, McKinnon said.

Eversource said it's still working to determine the cause of the outage and power surge, and any customers with additional concerns should reach out directly to the utility company. Crews will remain in the area Monday evening.

Belmont firefighters said on Twitter that they were responding to Waltham to cover their quarters after a large power surge was reported in the city. Cambridge firefighters said they also responded to the city.

The Weston Fire Department said on Facebook that it was covering Waltham and responding to numerous incidents while firefighters there dealt with "a major power issue."

The cause of the fire remains under investigation as Eversource says power has been restored to all of its customers.