Federal authorities are investigating former city police commissioner Bernard Kerik for his involvement in a foundation that he oversaw while head of the city's Correction Department, according to published reports Friday.

The inquiry by the FBI and federal prosecutors focuses on possible financial improprieties involving the foundation, which was run by the Correction Department, according to published reports.

The Daily News reported in 2003 that the foundation failed to report how it spent nearly $1 million in cash rebates earned from cigarette sales to prisoners.

In 1995, the foundation asked tobacco companies to send checks to the city. Under an earlier rebate program, city jails would receive promotional clothing, sporting goods and other merchandise in exchange for rebate points on cigarette packs.

The newspaper reported at the time that Correction Department officials said they used the rebate money to produce promotional videos and throw holiday parties for inmates, but that they refused to release documents itemizing the foundation's spending.

The group's treasurer, then-deputy police commissioner Frederick Patrick, pleaded guilty in July 2003 to stealing more than $137,000 from the foundation. He was sentenced to a year and a day in prison, a term that ended last July.

News of the investigation comes more than a month after Kerik pleaded guilty to charges that he accepted tens of thousands of dollars in gifts while he was correction commissioner. The federal probe is not related to those charges, The New York Times reported Friday.

Regarding the federal inquiry, Kerik's lawyer, Joseph Tacopina, told the Times: "I'm not going to justify a rumor like that with a comment."

Kerik first drew national attention while leading the police department's response to the Sept. 11 terror attacks.

By late 2004, President Bush wanted him for homeland security chief, but he withdrew after acknowledging he had not paid all taxes for a family nanny-housekeeper and that the woman may have been in the country illegally.