A leading private investigator has unearthed bombshell new evidence that tragic diva WHITNEY HOUSTON was murdered – and he’s taking it to the FBI to get the case reopened.

The ENQUIRER has learned exclusively that Paul Huebl, a former Chicago police investigator and now a top Hollywood private eye, plans to pres­ent his secret dossier to the bureau’s Chicago office – revealing shocking evidence that details who killed Whitney and why.

In a sensational disclosure that can crack the case wide open, Huebl says he’s received a tip from knowledgeable sources that Whitney’s killers are actually caught on hotel videotape, and he’s contacting FBI agents to take a fresh look at the case he believes local authorities bun­gled or covered up.

“I have evidence that points to Whitney being a victim of high-powered drug dealers who sent thugs to collect a huge debt she owed for drugs,” Huebl told The ENQUIRER.

The veteran investigator believes he is close to learning the identity of the vicious killers.

He says they are two men from a group of scruffy hangers-on – unknown by Whitney’s usual en­tourage – who kept showing up in the days before the singer’s untimely death at age 48.

 His confidential informants insist that close examination of the surveillance videos from the Bev­erly Hilton hotel, where Whitney died, will show two shadowy characters entering and leaving her suite right around the time she died.

Ever since America’s greatest female singer was found floating face-down in a scalding-hot bathtub on Feb. 11, 2012, Huebl has relentlessly gone after her suspected killers.

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