Doctor prescribed Prince oxycodone under the musician's friend's name

On Monday morning, officials in Carver County, Minn., unsealed search warrants that had been filed secretly past year as part of their ongoing investigation into the death of Prince Rogers Nelson, who was found collapsed in an elevator in his Chanhassen, Minn., estate on April 21, 2016.

The documents also show the extent to which detectives went to track down the source of the synthetic fentanyl that an autopsy determined was the drug that killed Prince. Some pills in other bottles were marked "Watson 853", a label used for a drug that is a mix of acetaminophen and hydrocodone, another opioid painkiller.

A suitcase was discovered next to Prince's bed on the day he died and among the items inside, there were prescription pill bottles in Johnson's name - none of which were the medication prescribed by Schulenberg.

According to the warrants, authorities searched his estates as well as looking through the star's mobile phone records and email accounts. As for his secret alias, the papers said, "Judith confirmed that Prince would use the name "Peter Bravestrong" when he would travel..." The bottles were under his bodyguard Kirk Johnson's name. Dr. Schulenberg met with Prince and prescribed him clonidine, hydroxyzine pamoate and diazepam, which were filled on April 20 at Walgreen's on County Road 101 in Minnetonka. Prince's private jet made an emergency landing at the airport in Moline, Illinois.

Some of our favourite beloved famous faces who have passed away in 2016. Schulenberg said he placed the prescription under Prince's bodyguard's name, the documents state.

April 21, 2016: Shortly after arriving at Paisley Park about 9:30 a.m., Andrew Kornfeld and two Prince staffers - longtime friend Kirk Johnson and personal assistant Meron Bekure - find Prince's body in an elevator.

The documents, which were released on Monday, April 17, state that witnesses told authorities that Prince "recently had a history of going through withdrawals which are believed to be the result of abuse of prescription medication".

Almost everyone who was close to Prince - and who has been willing to speak to the media - said they never saw him taking any drugs.

And the former attorney for two of Prince's dead siblings says they had revealed Prince had an addiction to Percocet decades ago. The suitcase also contained lyrics for the song "U Got the Look" that appeared to be in Prince's handwriting.

Schulenberg did not immediately respond to ABC News' request for comment. Investigators interviewed Johnson sometime after Prince's death, and he told them Prince had gone to a local medical center for an illness in 2014 or 2015. Recovery Without Walls is a California-based prescription drug and alcohol addiction program run by Dr. Howard Kornfeld.

Investigators have said little about the case over the previous year, other than it is active.

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