Russell Poole, a retired Los Angeles Police Department detective and the lead investigator in the murder of The Notorious B.I.G., has died. According to the Los Angeles Times, L.A. County sheriff’s deputies at the Homicide Bureau reported that Poole passed away Wednesday morning (Aug. 19) after collapsing during a meeting with detectives. Poole was rushed to a local hospital, where he died. TMZ reports that Poole died of a heart attack while interviewing an L.A. County Sheriff's captain about Biggie's murder. Poole was interview the captain for a book he was writing about Biggie's murder case. The L.A. County Coroner's Office conducted an autopsy but still do not know the cause of death and are waiting for toxicology results.

The former detective worked on Biggie's case for about a year. During that time, he gained a lot of attention in his department for his theories about the late rapper's killer. B.I.G., born Christopher Wallace, was slain on March 9, 1997 as he was leaving a Soul Train Music Awards after party. The shooting took place six months after Tupac Shakur was murdered in Las Vegas. Poole believed that the two cases were related. He also believed that Wallace's murder involved a conspiracy between a corrupt LAPD detective and Suge Knight, the head of Death Row Records, the label to which 'Pac was signed. Poole later went on to write LAbyrinth: A Detective Investigates the Murders of Tupac Shakur and Notorious B.I.G., the Implication of Death Row Records' Suge Knight, and the Origins of the Los Angeles Police Scandal; in an unrelated case, Suge Knight is currently in jail on murder and attempted murder charges stemming from a hit and run near the set of Straight Outta Compton that occurred earlier this year.

Poole's theories upset many in his department, and Russell was ordered to end his investigation by then-police chief Bernard C. Parks, which led to Poole's retirement in 1999. According to Billboard, Poole was under the impression that the department wanted to keep him from the truth, fearing a scandal. The department later tried to keep Russell from going public with his information, to which he responded by filing a suit against the LAPD for violating his First Amendment rights. After leaving the department, he went on to work as a private investigator. To this day, no arrests have been made in connection with either Biggie or Tupac's murders.

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