Days after Rudy Giuliani said Zohran Mamdani should stay away from New York’s 9/11 commemoration, the city’s first Muslim mayor released more than 170,000 pages of records that cast fresh scrutiny on what officials knew about toxic air in the aftermath of the attacks — including during Giuliani’s administration.

The documents, released Tuesday ahead of the 25th anniversary of the Sept. 11, 2001, attacks, detail health concerns, air quality around Ground Zero and the city’s response after the World Trade Center towers collapsed.

Their release followed a settlement with 9/11 Health Watch, an advocacy group that had pursued legal action to obtain records that remained out of public view for years.

"These are documents that show what the city knew about the toxic air around Ground Zero, when they knew it, and how they acted to limit liability,” Mamdani said.

Some of the records concern decisions made while Giuliani was mayor, including an internal memo sent to his deputy mayor outlining potential legal liability arising from hazardous air exposure and unsafe working conditions after the attacks.

Mamdani accused previous city leaders of misleading New Yorkers about the risks.

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

The release came shortly after Giuliani, who led New York during the 2001 attacks, publicly urged Mamdani not to attend events marking their 25th anniversary.

"Having lost friends there and being very close to many of the families, it offends me that he’s coming,” Giuliani said.

Giuliani also criticized Mamdani’s Muslim faith in making his case against the mayor’s attendance.

Mamdani rejected calls to stay away and said he would attend the commemorations, stressing that the anniversary should focus on the victims, their families and first responders rather than politicians.

"I love the city, I love this country,” Mamdani said. "My focus will be on attending events that memorialize that incredible courage and I will be there, just as I was last year.”

Asked following the document release whether Giuliani should instead stay away from the ceremony or whether the former mayor had lied about the air quality, Mamdani declined to turn the commemoration into a dispute between political figures.

He said New Yorkers could make their own judgment about responsibility.

The newly disclosed records show city officials had information raising concerns about hazardous conditions around Ground Zero even as residents, workers and first responders received assurances that the air was safe.

One document prepared for Giuliani’s deputy mayor, Robert Harding, discussed potential lawsuits against the city, including claims that health advisories had encouraged people to return to the area too quickly and exposed them to toxins.

Other records detail concerns about asbestos and other contaminants in Lower Manhattan.

9/11 Health Watch Executive Director Benjamin Chevat said four mayoral administrations had withheld records showing what the city knew about toxic chemicals in Lower Manhattan and western Brooklyn while officials continued publicly describing the air as safe.

More than 9,400 people have died from illnesses linked to exposure to the area since the attacks, according to a federal medical monitoring program.

The Sept. 11 attacks themselves killed 2,977 people after hijackers seized four passenger planes. Two were flown into the World Trade Center towers, another struck the Pentagon and a fourth crashed near Shanksville, Pennsylvania, after passengers fought the hijackers.

The Mamdani administration plans to release additional records over the next 12 months as the city continues reviewing the material.