Singer-songwriter Prince had an “exceedingly high” level of fentanyl in his body when he died,  according to a report obtained by The Associated Press.

The legendary musician, who was found unresponsive at his Paisley Park estate on April 21, 2016, had the drug in his system when he died from an accidental overdose, according to public data.

Fentanyl is an opioid that is used to treat pain but is considered to be extremely dangerous and “50 times more powerful than heroin.”

Experts agreed that fentanyl was the most likely culprit that caused his death and it was “a pretty clear smoking gun.”

“The amount in his blood is exceedingly high, even for somebody who is a chronic pain patient on fentanyl patches,”  Dr. Lewis Nelson, chairman of emergency medicine at Rutgers New Jersey Medical School, told the AP.

Law enforcement found many pills around his home, according to search warrants released a year after his death, AP reports.