A worker has died after the partial collapse of a crane and parking garage under construction at Government Center on Saturday evening, authorities said.
The collapse occurred at 1 Congress St. around 5:40 p.m., officials said.
Police said a man who was operating a crane was killed when his crane came down approximately nine stories with a large amount of debris. The worker's name has not been released.
A passerby was also taken by Boston EMS to an area hospital but was not physically injured.
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"This is a horrible tragedy and my heart goes out to the family and loved ones of the worker here tonight," Boston Mayor Michelle Wu said.
"Our thoughts and prayers are with the worker during this terrible time," added City Councilor Ed Flynn, who represents the neighborhood. "Our prayers are wit him, his family, and I know the city will support that worker and his family. It's a difficult time, but this city sticks together -- especially during difficult times."
The demolition is all part of the $1.5 billion Bullfinch Redevelopment Project. The finished project is expected to include a parking garage surrounded by office and apartment buildings. The site has been under demolition for some time.
"This is a very complex site and we know that the workers who take on the risks of this should never have to worry about, their family should never have to worry about if they're going home at night," Wu said.
She said the city will do "whatever it takes to know what happened here."
The Occupational Safety and Health Administration is on scene investigating the collapse.
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The project is located right over a series of Massachusetts Bay Transporation Authority Orange Line tunnels, and public safety officials are currently working to ensure the stability of the parking garage and the tunnels underneath. As a result, major traffic impacts are expected on roadways and on the MBTA for the next several hours.
"Right now a major area of this part of the city is quarantined until we can determine it's safe and the tunnel tracks underneath are safe," Boston police Capt. Kelley McCormick said.
Boston police have issued a traffic advisory along Massachusetts Avenue between Commonwealth Avenue and Boylston Street, which will be closed until Monday morning for construction. Travelers are advised to seek an alternate route.
"We'll be working very quickly to make sure as soon as possible, transportation, traffic and everything can resume," the mayor said Saturday night. "We're asking folks to be patient."
John Moriarty & Associates, the company which is overseeing the construction, confirmed that one of its workers had died at the site after a concrete slab fell from the ninth floor on the east side of the Haymarket garage and collapsed onto the eighth floor.
"Our heartfelt thoughts and condolences go out to the loved ones of the worker who lost his life," read a statement from the company. "JMA remains committed to providing a safe and healthy workplace for all our employees and trade partners."
Suffolk County District Attorney Kevin Hayden's office also released a statement, saying that it will be involved in investigating the tragedy.
"Our office is a stone’s throw away from the garage and our staff has watched through their office windows all the work being done these many months," Hayden said in the statement. "To know that one of the workers on this project has tragically died weighs heavy on our hearts. Our deepest sympathies go out to his family and friends."