Tests reveal that Prince died of an opioid overdose, a law enforcement official told The Associated Press.

This confirms suspicious that opioids were behind the death of the legendary musician, 57, who was found dead on April 21 at his sprawling estate in the Minneapolis area.

The law enforcement official spoke to the AP on condition of anonymity because he was not authorized to speak with the press.

It was reported that Prince was set to meet with an addiction specialist doctor on April 22, the day after he died. The specialist, Dr. Howard Kornfeld, was not able to see Prince fast enough, so he instead sent his son, who called 911 when the singer was found lifeless. The son was carrying buprenorphine, a medication that is used to treat opioid addiction. A lawyer for the Kornfelds said he fears the son will be charged "but has confidence the son will not be prosecuted since he was the person who called authorities," reports Billboard.

"DEA agents obtained a search warrant for Prince's Paisley Park estate earlier this month, revealing that Prince had met with a doctor at his home the day before he died," reports People. "The papers did not disclose which illness Prince was diagnosed with, but indicated that the doctor had performed tests on the star and prescribed him with medication. 

"While Prince's longtime lawyer L. Londell McMillan insisted that the 57-year-old was 'not on any drugs that would be cause for concern,' and that he lived a clean lifestyle, sources confirmed to PEOPLE that he had a history of using Percocet." 

Since Prince's death, members of his family have been in court to settle his $100-million-plus estate. Last week, the judge in charge of the case authorized genetic testing of a blood sample from Prince to help determine who in fact is entitled to his estate.

"At least a couple of people claiming to be Prince's children from unmarried liaisons have filed claims. If they can establish parentage, they would get it all," reports the Minneapolis Star Tribune. 

A funeral for Prince will occur in August, according to his sister, Tyka Nelson. A smaller, informal ceremony was held at Paisley Park the weekend after he died.