The investigation into Lil Peep’s death is still ongoing as police are looking into whether fentanyl, a highly potent opioid, played a part in the rapper’s death.

Billboard reports that police in Tucson, Ariz., have received “multiple tips” and are currently investigating whether Lil Peep was in possession of illegal prescription drugs laced with the lethal synthetic anesthetic.

"Detectives were initially investigating whether any foul play was involved, as they do with any death, especially suspicious deaths when a young person is killed," said Tucson Police Department spokesperson Officer Chris Hawkins. "Detectives are also looking into what kinds of drugs he ingested and what was in those drugs, especially since illegal prescription drugs often contain fentanyl, so it wouldn't surprise me to see if there was some fentanyl in there."

Fentanyl, which is 100 times more powerful than morphine and much more potent than heroin, is often mixed with other drugs to increase their potency, mostly without the user's knowledge. The drug has been linked to the death of Prince in April 2016.

Lil Peep, whose real name is Gustav Åhr, passed away at the age of 21. There has been no confirmation of a drug overdose.

A police report revealed that the late rapper went to take a nap before his Tucson, Ariz. show and never woke up.

Hawkins told Billboard, that investigators will try to determine what drugs were in Peep's system at the time of his death, and how he obtained those drugs, since fentanyl can been found on the black market in the Tucson area.

"Some people have reached out with tips about where the drugs may have come from or how he came in contact with them," said Hawkins, adding that it's not confirmed that fentanyl was a factor and that officials won't know until the results of the toxicology tests are returned in several weeks.

Reps for Lil Peep had no comment.

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