The New York City mayor said the document release shows victims were ‘lied to’ about health impacts from the attacks.

Just days before the 25th anniversary of the September 11, 2001 attacks, New York City has released a trove of previously undisclosed documents suggesting government efforts to downplay – or even mislead – residents about dangerous air quality following the attacks.

At a news conference on Tuesday, Mayor Zohran Mamdani announced the publication of 170,000 pages concerning health issues following the collapse of two skyscrapers in the World Trade Center complex, known as the Twin Towers.

Mamdani said the effort would deliver “accountability around city government’s response to September 11 that New Yorkers have been denied for years”.

His remarks reinforced long-running suspicions that leaders in the United States prematurely allowed workers and residents back into area around Lower Manhattan where the towers fell.

“It would be one thing if government had stood alongside survivors and provided them with everything they needed at every step of the way. And yet, we know that could not be further from what actually happened,” Mamdani said.

“People got sick because the leaders they trusted lied and told them they were safe to breathe in toxic air.”

During the September 11 attacks, the Twin Towers were struck by two hijacked planes, leading to their collapse and the deaths of 2,753 people on site. The destruction sent a cloud of dust across Lower Manhattan. Fires burned in the rubble for months.

Thousands of police officers, firefighters and construction workers spent time working in the soot, often without proper protection.

Within weeks of the collapse, employees and residents were also allowed to return to nearby buildings, including One Liberty Plaza, which had sustained damage during the attacks.

But many of those who worked or lived around the site, known as “Ground Zero”, have seen their health decline in the years since. Some developed respiratory or digestive-system ailments that appeared almost immediately. Others have fallen victim to illnesses that developed over time, including cancer.

Read More: Mamdani releases records on toxic air in New York after 9/11 attacks