A worker noticed cracks in the concrete slab on the 22nd floor. He went down one level. What he saw there sent everyone out of the building.

The Manhattan high-rise at the center of this week’s emergency — the former Pfizer headquarters on East 42nd Street, currently being converted into apartments — is now the subject of a formal inquiry by New York City’s Department of Investigation, the city’s independent watchdog agency.

That escalation matters. What began as a structural failure is now a question of accountability.

What Went Wrong

Two support columns buckled under load, causing floors to sag — some by as much as four inches.

Nathan Berman, founder and managing principal of MetroLoft, the developer behind the project, offered an explanation to CNN. The company was adding 18,000 square feet across 15 upper floors. That additional weight, he said, proved too much for column supports that had not been adequately prepared for it.

The columns bent, in his words, essentially because they were either not properly reinforced or were missed entirely during the reinforcement process. He said the precise cause would be determined in due time.

City officials noted that the failed columns sit at the junction between the building’s existing structure and the newly constructed floors above — the seam where old meets new.

Two Versions of How Dangerous It Was

Here the accounts diverge.

MetroLoft maintains that no portion of the building was ever at risk of collapse.

City officials described the structure on Tuesday as unstable and established a formal “collapse zone” around it — evacuating neighboring buildings and closing surrounding roads.

Those are not compatible characterizations, and the gap between them is likely to feature in whatever investigation follows.

The Evacuation

The people who caught it first were the workers on site.

Sean Dow, a shop steward with Steamfitters Local 638, described the sequence. He noticed cracks in the slab on the 22nd floor. He went down a level. There, he saw the columns bending.

“We decided it was time to evacuate the building,” Dow said.

Crews then moved into emergency mode, deploying jacks and installing new steel supports to shore up the compromised sections. Officials later expressed confidence that the building had been stabilized.

Who Is Investigating, and Why It Escalated

Multiple agencies are now involved.

The Department of Buildings has committed to a full investigation covering how the failure occurred, what led to it, and how comparable incidents can be prevented. Its process will include:

• Review of construction documents
• Interviews with witnesses
• Examination of available video and photographic evidence from the site

The department has also required the building’s owner to retain a third-party engineer to perform a forensic evaluation identifying the root cause.

But the Department of Investigation’s entry changes the character of the inquiry. DOI investigates fraud, corruption, misconduct, municipal malfeasance, city employees, contractors, and anyone doing business with the city.

When it finds evidence of criminal conduct, it routinely coordinates with prosecutors and law enforcement to pursue charges alongside any administrative or civil action.

CNN has reached out to the Manhattan District Attorney’s office.

A Tangled Web of Responsibility

Investigators face a structural problem of their own: figuring out who is actually responsible.

Major New York construction projects typically involve multiple developers, general contractors, subcontractors, hundreds of workers, and numerous entities with distinct and overlapping duties.

Sorting out where the reinforcement process broke down — and who owned that step — will not be quick.

The Mayor Weighs In

Mayor Zohran Mamdani used the incident to defend the broader policy while condemning this specific execution.

Office-to-residential conversions, he said, are part of the answer to the city’s housing crisis. But safety and accountability come first.

“This is not a necessary consequence of an office-to-residential conversion,” Mamdani said. “This, however, is clearly a breakdown in that process.”

The Department of Buildings echoed the accountability point, stating that contractors and site safety professionals carry a legal obligation to maintain safe conditions — for their workers and for the public. Any enforcement actions await the investigation’s findings.

MetroLoft’s Existing Legal Problems

The developer was not entering this week with a clean record.

MetroLoft is already contesting a legal challenge exceeding $300 million over alleged dangerous defects and code violations at a Tribeca property it converted into high-end residences.

A condo board sued in 2022, naming Berman, another executive, and the project’s architect. The civil complaint alleges breach of contract, negligence and fraud, among other claims. Attorneys for the defendants have denied the allegations. The case remains active. MetroLoft declined to comment on the pending litigation.

Separately, a construction worker has sued over a “grave injury” sustained at the East 42nd Street site last year, alleging that wood he was standing on gave way beneath him. That case is unrelated to Tuesday’s failure.

What Comes Next

The building stands, stabilized. The workers are safe. The roads will reopen.

What remains unresolved is the question investigators must now answer: was this an unfortunate engineering miscalculation, or something that documents, interviews and evidence will reveal as preventable?

Given who is now asking, the answer will carry consequences either way.