Emergency crews worked Tuesday to stabilize a Midtown Manhattan high-rise after structural columns buckled and floors sagged inside the former Pfizer headquarters near Grand Central Terminal, forcing evacuations and street closures in one of New York City’s busiest districts, officials said.

The structural problems were found on the 21st floor of 235 East 42nd St., a 37-story building between Second and Third avenues, according to the Fire Department of New York. Officials said crews found multiple cracks and sagging floors after receiving reports of a structural issue shortly before 8 a.m.

No injuries were reported, and all workers at the construction site had been accounted for by early afternoon.

“It’s a very serious situation because the box beams-the steel beams-have started to bend and deflect from the weight,” FDNY Chief of Department John Esposito said in a statement. “We evacuated the building and started evacuations of surrounding buildings. The building has continued to move since we have been on the scene.”

Mayor Zohran Mamdani urged people to avoid the area as engineers and emergency officials assessed the damaged structure.

“The building remains unstable,” he said.

A 37-story Midtown Manhattan building being converted from offices into apartments was evacuated Tuesday after two structural columns buckled and floors sagged. (New York City Fire Department)

A 37-story Midtown Manhattan building being converted from offices into apartments was evacuated Tuesday after two structural columns buckled and floors sagged. (New York City Fire Department)

A “frozen zone” was established from 40th to 45th streets between First and Third avenues, closing the area to pedestrians and vehicles, according to city officials.

Firefighters, emergency medical workers, the Department of Buildings and NYC Emergency Management responded to the site. FDNY said its drones were being used to provide images and technical information to partner agencies while engineers evaluated the building.

Officials had not announced a cause for structural failure as of early Tuesday afternoon.

The building is part of a prominent office-to-residential conversion project at the former Pfizer headquarters. The project was expected to create more than 1,600 apartments, including more than 400 affordable units, according to Gensler, the architecture firm behind the project.

Gensler described the conversion as the largest of its kind in New York City history if completed as planned in 2027.

The incident comes as New York City has pushed to turn underused office buildings into housing, particularly in business districts where remote and hybrid work have left large amounts of commercial space vacant. Such conversions are often technically complicated because office towers were not designed with residential layouts, plumbing, light access and load distribution in mind.

A 37-story Midtown Manhattan building being converted from offices into apartments was evacuated Tuesday after two structural columns buckled and floors sagged. No injuries were reported, but city officials closed nearby streets and evacuated surrounding buildings while engineers assessed the risk. (New York City Fire Department)

A 37-story Midtown Manhattan building being converted from offices into apartments was evacuated Tuesday after two structural columns buckled and floors sagged. No injuries were reported, but city officials closed nearby streets and evacuated surrounding buildings while engineers assessed the risk. (New York City Fire Department)

Some workers and union representatives quoted by local news outlets raised concerns about support for the added construction load.

Metro Loft, the developer on the conversion project, said in a statement that safety was its top priority and that it was working with the Department of Buildings to understand the full scope of the situation.

“We’re thankful there were no injuries, and as the D.O.B. clarified, no debris fell from the building” the MetroLoft statement said. “We want to confirm that the affected area is a small section of one of the two buildings on this site. As the F.D.N.Y. spokesperson noted, the entire building itself is not at risk of collapse.”

Buildings Commissioner Ahmed Tigani said at a Tuesday news conference that engineers were evaluating the structure from outside and from nearby vantage points.

City officials said emergency beams and columns were being brought to the site so crews could shore up the affected area once it was safe to enter.

Mamdani said the situation was changing quickly.

“This is a minute-by-minute assessment,” he said.

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This article originally published at NYC crews race to stabilize high-rise after structural columns buckle.