Former New York City Mayor Rudy Giuliani is breathing on his own after being hospitalized with pneumonia and placed on a ventilator, his spokesperson said Monday, as Giuliani remained in critical but stable condition at a Florida hospital near Palm Beach.

Spokesperson Ted Goodman said Giuliani, 81, was breathing on his own and that the former mayor remained in critical but stable condition. Goodman said Giuliani was being monitored at the hospital as a precautionary measure.

Goodman said Giuliani’s pneumonia was made worse by what he described as restrictive airway disease attributed to Giuliani’s exposure to dust and toxins from the Sept. 11, 2001, attacks on the World Trade Center. Goodman said in a statement that the condition added complications to any respiratory illness and that a virus quickly overwhelmed Giuliani’s body, requiring mechanical ventilation to maintain oxygen and stabilize his condition.

Goodman said Giuliani’s hospitalization began after the 81-year-old was heard coughing Friday on his nightly online talk show, when he told viewers his voice was “a little under the weather.” Giuliani later described he would speak less loudly and get closer to the microphone.

Goodman said Giuliani’s family and primary medical provider were with him at the hospital. He said Giuliani’s family thanked well-wishers for an “outpouring of love and support,” adding that Trump, Israeli Prime Minister Benjamin Netanyahu and Giuliani’s successors as New York City mayor—former Mayor Eric Adams and current Mayor Zohran Mamdani—were among those offering support.

Goodman said Giuliani “believes in the power of prayer” and that “we are feeling that strength today.” He also said Giuliani was “the ultimate fighter” and told reporters, “he is winning this battle.”

Giuliani served as mayor of the nation’s largest city for eight years, and his tenure was marked by the Sept. 11 attacks a few months before he left office. He later unsuccessfully ran for president as a Republican, became an adviser to Donald Trump, and helped spearhead Trump’s efforts to stay in office after his 2020 election loss.

In addition to his political work, Giuliani had a career as a federal prosecutor and was elected mayor in 1993 after serving as one of the highest-profile prosecutors in the U.S., according to the account provided by Goodman through the spokesperson statement. The statement also noted Giuliani previously was hospitalized last September after a car crash in New Hampshire left him with a fractured vertebra and other injuries.