BOSTON (WBZ NewsRadio) — Two Eversource workers were hospitalized after an underground explosion near the state capitol Tuesday evening, fire officials said.
The explosion occurred shortly before 6 p.m. as an Eversource crew was performing routine maintenance in an underground electrical vault on Bowdoin Street.
Initially reported as a manhole explosion, fire officials later said the explosion was caused by a transformer.
Boston Fire Commissioner Paul Burke said there was a malfunction in the equipment they were working on that apparently caused the transformer to explode.
"They were performing regular, routine maintenance," said Burke. "There was some malfunction with the mechanical equipment that caused the explosion. They're very skilled workers, they know what they're doing."
After the explosion, witnesses saw smoke and fire billowing out of a manhole near the John McCormack State Office Building's parking garage, prompting a large fire rescue response blocking the road near Bowdoin and Cambridge streets. Fire crews worked with Eversource to cut off the power and put out a fire associated with the explosion.
"They were performing regular, routine maintanence
Eversource confirmed in a statement that two workers were sent to Massachusetts General Hospital, "one for severe injuries caused by the equipment flash and the other for smoke inhalation."
The statement added that Eversource "has launched a full and detailed investigation in close collaboration with local, state, and federal safety officials, as well as the leadership of UWUA Local 369."
OSHA is also investigating the incident.
The McCormack Building will be closed Wednesday as a result of the explosion.
This is the latest in a series of incidents in Boston involving manholes in recent months. Earlier Tuesday, Boston firefighters briefly shut down Congress Street after smoke was seen billowing out of a manhole at the corner of Quaker Lane. In June, two manhole covers blew off on High Street, sending one woman to the hospital. In May, fire burst from two manholes on Boylston Street.