Thousands of people were evacuated from the Kendall Square area Friday morning after a contractor dug into a high pressure line, causing a "major natural gas leak," the Cambridge fire department said.
Officials evacuated upwards of 5,000 people from 11 area buildings, Cambridge Assistant Fire Chief Tom Cahill told reporters. Those buildings included residences, businesses, day care facilities and others. No injuries were reported.
The fire and police departments first responded to a natural gas line break near the area of 100 Binney Street just after 8 a.m. on Friday, when the high pressure line was ruptured.
By 9:40 a.m., the gas lines in the area were shut off, the fire department said, but officials will continue to monitor air samplings in Kendall Square and in buildings affected by the leak.
Air samplings are still below the lower explosive limit, the lowests concentration of gas capable of causing a flash fire if ignited, officials assured.
However, it can take up to two to three hours for the gas to dissipate from buildings closer to the source of the leak, Cahill said.
"The source of the gas has been shut down, so overtime those explosive gases will dissipate with ventilation," he said. "It's a matter of waiting at this point."
Cambridge police will continue to maintain the evacuation zone Friday morning until the gas dissipates, and fire crews are working to ventilate those buildings to help the gas clear.
Police sent out an alert explaining that officials were on scene and informing those in the area that, "buildings in the immediate vicinity are being and have been evacuated to ensure the safety of those in the area; traffic is also being diverted.”
Eversource workers came to the scene as well, officials said, to shut down valves. Police redirected traffic around the area as a safety perimeter was established.
The leak did not happen inside 100 Binney Street, Cahill said, but in a construction area adjecent to that building.
"Anytime there's construction, there's always the possibility of any incident occurring," he said. "[However,] an incident of this scope is not common."