A wall of the building, located in Lower Manhattan at 60 Norfolk Street, partially collapsed, trapping the two workers underneath rubble around 10 a.m., officials said.
The two people were taken to nearby hospitals, where one – identified as Stanislaw Supinski, a 52-year-old Polish immigrant – was pronounced dead, and the other remains in serious but stable condition, WCBS-TV reported.
"They were on the surface, not totally buried," Michael Ajello, assistant chief of the FDNY, told reporters. "It was within five or 10 minutes that they were extricated and removed from the scene."
Some witnesses said the wall crumbling looked deliberate — as if the wall was being demolished.
"We didn't know that there were people under there, I mean, we were just talking like, 'Wow, can you see that?' One big piece just [went down] and then landed. Clean, like a clean shot," witness Robert Kaljaj told WABC-TV. "We thought that this was planned, because we saw the backloader kind of moving back and forth."
The building was once home to the Beth Hamedrash Hagodol congregation, and was landmarked by the Landmarks Preservation Commission in 1967 because of its "special character, special historical and aesthetic interest and value as part of the development, heritage and cultural characteristics of New York City."
Built in 1850, the temple ultimately closed in 2007, fell into disrepair and was burned down in a suspected arson in May 2017. The building is reportedly being transformed into a mixed-use building designed to preserve the synagogue's history.