Two workers injured in Beacon Hill manhole explosion

A large number of Boston police and fire vehicles were on the scene of the explosion at Bowdoin and Cambridge streets.Camilo Fonseca/Globe Photo

Two Eversource workers were injured after an underground transformer exploded on Bowdoin Street on Tuesday evening, according to officials.

One man was treated for severe burns, and the other man for possible smoke inhalation, said Jim Borghesani, a spokesperson for the Suffolk District Attorney’s office.

Dispatchers received reports of the explosion at 5:51 p.m., said Officer Stephen McNulty, a spokesman for the Boston Police Department. Police, fire and EMS crews responded to the scene across from 37 Bowdoin St., assisting with the incident and directing traffic, McNulty said.

Boston EMS transported the two workers to Massachusetts General Hospital, according to Boston Fire Commissioner Paul Burke.

The two workers were performing routine maintenance on the transformer when a “mechanical failure” occurred, Burke said. The precise nature of the failure is under investigation.

Burke added that electrical workers usually check the air quality before going down underground, to detect any explosive gases or fumes.

“They’re very skilled workers; they knew what they were doing,” he said.

Burke confirmed that the two men were the only workers onsite at the time of the explosion.

“It’s a sad situation,” he said. “Two workers just doing their jobs, and they get injured.”

Eversource responded to the incident just after 6 p.m., according to company spokesperson Christopher McKinnon.

“At this time, our focus is on our employees’ well-being and making sure they receive the medical treatment and support they need,” McKinnon said.

Several witnesses reported hearing the loud explosion, some from several streets away. Philip Gilpin, 61, said he turned the corner only to see the whole street covered in a “brown, smoky haze.”

Ravi Lala, 47, was exiting a nearby Target when he saw one of the workers emerge from the smoke, with his clothes “half burnt” and still smoldering.

The injured worker urged him and other bystanders to help tear his clothes off. Lala said the man was “overheated,” suffering from “diffuse burns” and in too much pain to stand still.

“All of this happened within maybe two minutes, before first responders arrived,” he said. “I have a healthy respect for first responders, putting their lives down on the line—especially after witnessing something like this firsthand.”

Parts of Bowdoin and Cambridge streets were temporarily closed to motorists and pedestrians, according to Massachusetts State Police. The underground fire appeared to be under control by about 7 p.m.

The Occupational Safety and Health Administration is aware of the two injured Eversource workers and is responding, said Edmund Fitzgerald, a local spokesperson for the federal labor department.