Cambridge Assistant Fire Chief Thomas Cahill told reporters at the scene that as many as 5,000 people had been evacuated.

“The leak was caused by a contractor digging into a gas line,” Eversource spokesman Michael Durand said.

CAMBRIDGE — Eleven buildings were evacuated in Kendall Square on Friday morning, disrupting the workday routine for thousands of people, as officials scrambled to shut down a gas main that had been accidentally punctured by a contractor operating heavy equipment, officials said.

The affected buildings included residences, businesses, and day care facilities, Cahill said.

No one was hurt.

He said a high-pressure gas main had been breached by a contractor working adjacent to 100 Binney St.


“Any time there’s construction, there’s always a possibility of any type of incident occurring,” Cahill said. “The gas lines were marked, and it was an accident.”

However, he said, “An incident of this scope is not common.”

Construction projects abound in the area, a booming hub for tech and biotech companies.

Most of the buildings affected by the gas leak were cleared for reentry a little after noon, fire officials said.

Cahill said firefighters went from building to building to check gas readings to make sure they were safe.

“The gas permeated up to 11 buildings,” he said. “People smelled the gas and began evacuating,” even before firefighters arrived.

Cahill said there was “no confirmed explosion.”

“We pushed everybody into a safe area,” Cahill said. “We just wanted to get them out of the hazardous area.”

Durand, the Eversource spokesman, said the gas had escaped into the atmosphere. “In a situation like this, what you want to have happen is exactly what happened,” he said.

Durand said the contractor, A.A. Will Materials, was believed to be doing “sidewalk work.”

Eversource was first notified of the incident around 8:25 a.m.


Workers shut down two valves, at the intersections of Linskey Way and Second and Third streets, and the gas was off by 9:25 a.m., according to Durand.

Eversource crews worked to replace the broken line, he said.

Durand said in a follow-up statement Friday afternoon that Eversource expected to complete the gasline repair work Friday evening. He said all streets had been reopened to traffic and all occupants were let back in their buildings.

Only one building remained without gas service as of 4 p.m., Durand said.

“Also, to reiterate from earlier, the cause of the gas line damage and gas leak was a contractor not affiliated with Eversource accidentally hitting the line during construction work in the area,” Durand wrote.

During the morning evacuation, hundreds of bewildered employees of businesses in the area stood on the street as television helicopters hovered in the sky.

Erma Caro, 53, of Revere, sat on the curb on Third Street and said she was heading into the Watermark building Friday morning for work but could not get in because of the evacuations.

“I came and I saw all the people,” Caro said.

Ronald Silva, 40, of Brighton, a Watermark custodian, said alarms had sounded in the building to get everyone out.

“It’s very stress[ful], because we have a lot of work to do inside,” Silva said.

Sue Gerngross, 63, was still waiting to get into her apartment building around 11:45 a.m.

“It’s kind of crazy, but it’s kind of fun to see who lives in my building,” Gerngross said, adding that she feels “sympathy” for people with young children who were forced to evacuate.


She said alarms went off in her building at the time of the incident.

“Someone knocked on my door and said, ‘You’ve got to go,’” Gerngross said. “And I was preparing to go.”

Officials scrambled to shut down a gas line that had been accidentally punctured by a contractor operating heavy equipment in Kendall Square. BOSTON 25 NEWS

Officials scrambled to shut down a gas line that had been accidentally punctured by a contractor operating heavy equipment in Kendall Square. BOSTON 25 NEWS

John R. Ellement of the Globe Staff contributed to this report. Ben Thompson can be reached at ben.thompson@globe.com. Travis Andersen can be reached at travis.andersen@globe.com.