Prince was alone at his Paisley Park studios when he died Thursday and his body showed no signs of violence or suicide, Carver County Sheriff Jim Olson said Friday.
Prince, 57, had been dropped off at the studios by an acquaintance around 8 p.m. Wednesday night, which was the last time he was seen alive, Olson told reporters. Paisley Park staff members went to the Chanhassen building Thursday morning to check on Prince after being unable to reach him.
The pop music icon was found collapsed and unresponsive in an elevator on the building's first floor. Attempts to revive him with CPR failed.
Prince was a very private person "and I don't think that would be unusual for him to be there by himself," Olson said.
The time of death isn't clear yet but it was not in the minutes before emergency personnel first arrived mid-morning, he added.
Olson declined to provide many more details, saying the investigation was only 29 hours old. He said Carver County authorities had not received any medical calls at Paisley Park involving Prince directly in the past year.
Olson's remarks came a few hours after the autopsy on Prince was completed. The Midwest Medical Examiner's Office in Anoka County said the body was released to family members in the afternoon.
Investigators they're pulling together information on Prince's medical and family history and are considering anything that could be relevant to the investigation.
"Gathering the results will take several days and the results of a full toxicology scan could likely take weeks," the medical examiner's office said, adding that no other information would be released until that work is complete.
Full coverage: Prince
Prince was reportedly treated last week for dehydration and flu-like symptoms in Illinois after an unscheduled stop of a plane he was on while returning from a performance in Georgia.
The chartered flight diverted and landed at Quad City International Airport at 1:18 a.m. on April 15, according to the website Flightaware.com.
"We'd received a call that (an) aircraft had an unresponsive person on the plane and we requested an ambulance," said Quad City International Airport Public Safety Manager Jeff Patterson. "We contacted the Moline (Ill.) Fire Department who responded with an ambulance. We escorted them to the aircraft and the Moline Fire Department transported the subject to a hospital here in the Quad Cities."
Patterson would not say who was on the plane, which remained on the ground in the Quad Cities for about 9 hours and 40 minutes and departed for Minneapolis at 11 a.m.
On Saturday night at Paisley Park, Prince threw a dance party and made a brief appearance to assure people he was fine.
Prince's health history and the circumstances involving the unexpected landing and hospital stop in Moline would be probed as part of the larger investigation in Prince's death, Olson and a spokesperson for the medical examiner's office said.
Olson called Prince a sound citizen in the community.
"We would see Prince from a law enforcement standpoint occasionally. He would have concerts at Paisley Park and we would help with the traffic assistance and those kinds of things," he said. "He lived in Chanhassen a long time and had two different residences not counting Paisley Park itself. He had been a longtime member of the community and, really, a good neighbor for everybody."