MINNEAPOLIS (AP) — The Latest on the investigation into the death of music superstar Prince (all times local):
A law enforcement official tells The Associated Press that investigators are looking into whether Prince died from a drug overdose and whether a doctor was prescribing him drugs in the weeks before his death.
The official says that among the things investigators are looking at is whether a doctor was on a plane that made an emergency landing in Illinois less than a week before Prince died.
The law enforcement official has been briefed on the investigation and spoke on condition of anonymity because he was not authorized to speak to the media.
The official says investigators are also looking into what kind of drugs were on plane and at Prince's house in suburban Minneapolis where the musician was found dead April 21.
- Associated Press writers Amy Forliti in Minneapolis, Michael Tarm in Chicago and Eric Tucker in Washington, D.C. contributed to this report.
A rundown of calls to police from Prince's Paisley Park estate in recent years is dominated by incidents like suspicious activity, trespassers or tripped alarms.
But the five-year summary released Thursday by the Carver County Sheriff's Office also includes four calls classified as medical.
One of those came on April 21, the day the 57-year-old musician was found unresponsive and later pronounced dead.
The sheriff's office didn't immediately respond to a request for incident reports on the other three calls.
But two of those calls came in the past year, when Carver County authorities say they received no medical calls to help Prince himself from his suburban Minneapolis home and recording studio complex.
The last call classified as medical came on Oct. 23, 2013.
A Minnesota judge has sealed a search warrant in the investigation of Prince's death after authorities argued that making it public would hamper their work.
The search warrant is for Paisley Park, the musician's home and recording studio complex in suburban Minneapolis. Prince died at the complex on April 21, and the search was carried out that day.
The local sheriff and prosecutor filed papers Thursday requesting it be sealed. They cited the intense media scrutiny following Prince's death.
The singer was found unresponsive in an elevator at Paisley Park, and was soon pronounced dead. No cause of death has been determined, and results from an autopsy aren't expected for three to four weeks.
Several news organizations are reporting that prescription drugs were discovered with Prince when he was found dead in his Paisley Park home.
ABC, NBC, CBS, and CNN, citing unidentified law enforcement sources, have reported that prescription painkillers were found on the 57-year-old Prince and in his home. The Star Tribune, also citing unnamed sources, reported that prescription pills were found but that it wasn't clear whether they were prescribed to Prince.
Prince died April 21. Autopsy results aren't expected for three to four weeks.
Several outlets also reported Minnesota investigators have asked the U.S. Drug Enforcement Administration for help.
Carver County Deputy Sheriff Jason Kamerud discounted those reports late Wednesday, saying the DEA "is not part of the investigation at this time." A DEA spokesman in Chicago declined comment.