His death followed a private battle with illness, FBI director Kash Patel said.

During Republican mayor Rudy Giuliani’s administration, he spent two years as the city’s commissioner of the department of corrections starting in 1998 before being appointed police commissioner in 2000.

He oversaw the response, rescue, recovery during the Sept 11 attacks before leaving the NYPD in December 2001.

Kerik was later nominated by president George W Bush to lead the department of homeland security during the early stages of the US’ war on terror.

“Bernie Kerik understands the duties that came to America on Sept 11. The resolve he felt that morning will guide him every day on his job,” Bush said in 2004.

The nomination was short-lived as Kerik withdrew from consideration days after.

His employment of an undocumented migrant as a nanny was later stated as the reason for his withdrawal.

In 2007, he was charged with lying to White House officials and with tax evasion.

He later pleaded guilty and was sentenced to four years in prison.

He was pardoned by president Donald Trump in 2020.