NEW YORK -- A burly bodyguard who was shadowing Upper East Side madam Anna Gristina's every move for years was actually a moonlighting NYPD detective, sources said.

Sylvan "Sly" Francis was the hockey mom's right-hand man and rarely left her side when she came to New York City from her sleepy suburban home, the sources said.

The two were photographed casually holding each other in 2001 during Francis' two-year stint as her muscleman.

At the same time, Francis was assigned to the district attorney's squad assisting prosecutors with investigations.

The 54-year-old brute retired from the NYPD in 2002 after a decade in the department. One of his career highlights was working as a driver for a first deputy commissioner under Ray Kelly.

Manhattan DA investigators learned of Francis' involvement with Gristina only after seeing the photo in the New York Post alongside an exclusive jailhouse interview with the madam -- in which she revealed that prosecutors were desperately seeking dirt on 10 New York City powerbrokers.

Now the DA is scrambling to determine whether Francis helped provide some of the law-enforcement protection she had bragged about on wiretaps.

Prosecutors have said Gristina, a 44-year-old mom of four who lives in upstate Monroe, insisted she had friends in high places -- including cops, FBI agents and politicians.

The Manhattan DA's Office was caught flat-footed by Francis' involvement with Gristina -- despite having investigated her for five years, sources said.

"They just found out about this," a law-enforcement source said.

The source said prosecutors are in "circle-the-wagons" mode as they probe Francis' relationship with the woman they are accusing of running a 15-year escort service for the rich and famous.

"Now they're going to go back and look at his record when he was working in the office," the source said.

"I'm sure they're going to want to talk to him," the source added.

But one law-enforcement source said that despite the fact that Francis was working for the DA's office, he actually served in a different unit than the one investigating her.

"He worked in 'The Squad,' and this whole thing was out of [the Investigation Bureau]," which is comprised largely of retired detectives, the source said.

"One had nothing to do with the other," the source added.

A Manhattan DA spokeswoman declined to comment when asked about Francis.

Robert Morgenthau, who was the district attorney when Francis worked there, said he did not know the detective.

Asked about Francis' working for Gristina and the photo of her on his lap, Morgenthau said, "He was a Police Department employee, not a DA employee. That's a matter for the police."
The NYPD would not comment.

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