LOS ANGELES (CBS) — LAPD cop-turned-author Greg Kading is rekindling the debate about the two most famous and unsolved murders in hip hop history — Tupac Skakur and Christopher Wallace, a.k.a. Notorious B.I.G.

“It just didn’t sit right to have two cases that were right on the verge, especially these two cases, that were right on the verge of being solved,” Kading said.

After 22 years with the LAPD, the retired detective is revealing how close he says they came to significant leads before the task force was shut down.

His theory – outlined in the new book “Murder Rap” – goes back to the original theory of an East Coast/West Coast rivalry.

Kading says he copied audio tapes and statements that contained a confession by a gang member from LA’s Southside Crips.

“He told us that he had made an agreement with Puffy Combs to kill both Suge Knight and Tupac Shakur for the sum of $1 million,” Kading said.

Kading also says they got a female friend of Suge Knight’s to confess in the LA slaying of Biggie Smalls.

“She confessed to us that she was involved in the communications with Knight to carry out the murder and she facilitated the payments to the hit man,” he said.

But an original investigator told us by phone Friday he doesn’t buy a bit of this theory saying that a lot of people confessed a lot of things.

Russ Pool maintains Suge Knight masterminded both allegedly with the help of LAPD officers moonlighting as security guards.

“I’m absolutely confident that the LAPD had nothing to do with this,” Kading said.

Firm in his assertions, but in an email to LA Weekly, Sean Combs, a.k.a. P. Diddy told them “this story is pure fiction and completely ridiculous.”

When the task force was initially shut down, LAPD captains initially said they’d exhausted their leads but recently, an LAPD spokesperson said the investigation was open and ongoing with no further information available.

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