Prince: 'Prescription pills found at death scene'

Pop superstar Prince had no known will, his sister has said.

Tyka Nelson has filed paperwork to be appointed executor in state court in Minnesota.

The 57-year-old superstar was found dead in an elevator at his Paisley Park Studios compound in Minneapolis on Thursday. No cause of death has yet been released.

• Pop icon Prince 'cremated in private ceremony'

Ms Nelson, who is his only surviving full sibling, said in the documents that an emergency exists because immediate action is necessary to manage Prince's business interests.

He is believed to have left around $27 million (£18.5 million) in property and a spike in sales of his music since his death is likely to boost the wealth of his estate.

It is not known exactly how much Prince was worth when he died.

Prince stayed awake for 154 hours before his death, his brother-in-law has claimed.

Maurice Phillips reportedly claimed the 57-year-old singer had worked for six days without sleep when friends and family held a private service at the compound on Saturday.

Mr Phillips, who is married to Prince's sister Tyka Nelson, is said to have told fans outside Paisley Park: "He worked 154 hours straight. I was with him just last weekend. He was a good brother-in-law."

The mayor of Chanhassen, the city which is home to Paisley Park, where Prince lived, said discussions were taking place to stage a public service in honour of the superstar.

"It's clear his friends and family would support the idea," Denny Laufenburger said.

A private funeral service at a local church is expected to take place in early May, he added.

Prince was found collapsed in a lift by staff members on Thursday morning, more than 12 hours after he was last seen alive when he was dropped off at Paisley Park.

Prince's body has been cremated in a private family ceremony, according to reports.

Family and friends were seen arriving at Paisley Park on Saturday, where it is believed a private memorial was held.

The Associated Press, citing publicist, said that Prince's body had been cremated and a celebration of his life had been held.

The pop icon, a Jehovah's Witness who died aged 57, is said to have been secretly cremated after his body was released to his family on Friday afternoon, following a post-mortem examination.

There is no indication that Prince took his own life, Carver County Sheriff Jim Olson said.

Sheriff Olson added that there were no obvious signs of trauma on the singer's body.

However, police are investigating whether the singer's death involved foul play.

Speaking at a press conference at Carver County Courthouse in Chaska, Minnesota, Sheriff Olson refused to comment on reports that Prince had consumed a powerful painkiller before his death.

He said Prince was last seen at 8pm the night before his death when he was dropped off at his Paisley Park estate.

The singer had been alone at the estate and staff member had been unable to reach him, Sheriff Olson added.

A spokeswoman for the Midwest Medical Examiner's Office said it would not release information from the post-mortem examination until "all results are obtained", and added that the findings of a toxicology scan "could likely take weeks".

A four-hour post-mortem examination has been carried out on Prince's body following his sudden death on Thursday at the age of 57.

The singer's body will be released to his family later today, the Midwest Medical Examiner's Office said.

• Global tributes as pop superstar Prince dies aged 57

Jennifer Hudson led the cast The Color Purple in an emotional tribute to Prince on Broadway after the singer's death was announced.