Multiple crews were on the scene of the explosion that happened across from 37 Bowdoin Street in Beacon Hill around 6:30 p.m. on Tuesday, July 12, Boston Fire said on Twitter.
The explosion sent workers to Mass General Hospital, one suffering from severe injuries and the other for smoke inhalation, Eversource said on Twitter. The workers were apparently injured while working on underground equipment.
"There was some malfunction with the mechanical equipment that caused the explosion," said Boston Fire Commissioner Paul Burke, according to CBS Boston. "They're very skilled workers, they know what they're doing."
Witnesses described the scene as "blood-curdling" and eerily similar to the Boston Marathon Bombing, NBC10's Eli Rosenburg said on Twitter.
"All of a sudden, I hear 'pop, pop, pop boom,' louder than anything," one person said. "This brought memories back of the Boston Marathon."
"I could see his skin," neighbor Jose Rosario told CBS Boston. "He was just screaming, like it came from a horror movie. He was screaming."
The explosion shut power down to the area and the incident is being jointly investigated by Eversource and OSHA, the outlet reports.
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