The accident happened on Governor Winthrop Boulevard in New London behind the Garde Arts Center, the city announced at about 12:30 p.m. on Monday, April 25.
Fire officials, police, and the Occupational Safety and Health Administration are investigating the incident, the city said.
Governor Winthrop Boulevard was partially shut down, with traffic being rerouted at the time of the announcement.
The city said the public should avoid the area if possible.
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