A  building collapse in New York City’s borough of Brooklyn has killed at least eight people, with more injured as firefighters continue working to rescue potential survivors trapped under heaps of rubble.

At least 18 people have been hospitalised with injuries, including four in critical condition after the building came down on Wednesday afternoon. Four firefighters were among those being treated.

The collapse of the three-storey mixed-use building, which was built in the 1930s, occurred in a Flatbush area neighbourhood that is home to a predominantly Black and Afro-Caribbean community.

Rescue operations began around 4pm local time (21:00 GMT) on Wednesday and are ongoing.

New York City Mayor Zohran Mamdani shared updates about rescue operations on X, warning New Yorkers to avoid the area.

About 250 firefighters were working the scene, the mayor said, with many using power saws and pickaxes to tear through the debris during the early hours of Thursday.

Writing on X, he added: “There are no words for a loss of this magnitude. My heart is with the families and loved ones of those we have lost, those who are injured and everyone grieving today.”

Among those killed are two children and six adults, the mayor announced during a press conference on Thursday.

“If there is anyone, or any entity, operating in this city that bears responsibility for what happened, we will hold them fully accountable,” added Mamdani.

Pooling city efforts together

First responders arrived at the scene one minute after the first emergency call, according to Mamdani, who held a news conference at about 8pm on Wednesday (01:00 GMT Thursday).

New York City Fire Department (FDNY) Chief John Esposito said the crew was returning from a nearby emergency and immediately began search-and-rescue operations, according to CNN.

The building had toppled into a nearby construction site, trapping residents and construction workers inside, said FDNY Commissioner Lillian Bonsignore.

“We always assume there are more people there until we can access the ground. So until we remove some of the bigger debris and are able to search beneath them, this will remain a rescue operation,” said Bonsignore.

New York City’s Emergency Management set up a help centre for those impacted by the collapse at the local Flatbush YMCA.

Scores of firefighters and police officers wielding pickaxes and power saws clambered over the rubble pile overnight, punching holes through the ruins to pull dust-covered people from beneath piles of twisted wood and brick.

New York City Police Department officers were patrolling the site and emergency medical services personnel were working alongside rescue crews.

“The units are performing dangerous and heroic work,” Bonsignore said. “They encounter dangerous and perilous conditions. The risk of disrupting the piles by moving too quickly there … can have a detrimental consequence.”

Bonsignore added that the collapse will require a “prolonged operation”, with its cause still under active investigation.

A closer look at those affected

The Consulate of Ecuador in New York said Jose Luis Caguana Cosquillo from Ecuador was among those found dead.

His brother, Carlos, told WNBC-TV that he died while working at the construction site. He was an immigrant from Ecuador who had been in the US for about six years and had a pregnant wife and a young child, Caguana said.

“He was the sole provider for the family. Now that he’s gone, she is going through an immense amount of pain,” Caguana said.

A pregnant woman had been rescued from the site.

Site inspections conducted this year revealed several regulatory infractions

On Wednesday night, New York City Buildings Commissioner Ahmed Tigani noted that when the building fell, construction workers were excavating an empty lot next door for a new building.

Municipal authorities confirmed that a stop-work order had been enacted in March for the site, after inspectors determined the adjacent demolition lacked essential overhead safeguards, such as protective netting to shield neighbouring structures.

But in April, inspectors found that the demolition work had resumed in violation of the stop-work order, the department said, adding that the construction was allowed to continue in May after the problems were corrected.

Flatbush Resident Dervie Mapp, who lives along the construction site, told The Associated Press news agency that she and others complained for months about the project.

Her landlord brought engineers into the building, but residents never received an inspection report, she said.

Inquiries requesting comment were sent by the AP via phone and email Wednesday to the project’s architect, property owner and general contractor, as identified in municipal records. None have responded.