Prince died of an accidental overdose of the painkiller fentanyl in April. Fans embrace near a makeshift memorial outside Paisley Park, the home of the late rock superstar. [Photo/Agencies]

Prince, 57, left no known will. The judge overseeing the case has not ruled on who his heirs will be. But court filings indicate they'll likely include Tyka Nelson and five half-siblings because Prince was divorced, his parents are dead and he had no confirmed children.

Bremer Trust said the family supports the museum plan. The court has not ruled on whether a woman and girl who say they're Prince's niece and grandniece are entitled to share in the estate, which Bremer Trust has said could be worth up to $300 million.

The criminal investigation into his death is continuing. Some of the pills taken from Paisley Park after his death were counterfeit drugs that actually contained fentanyl, a synthetic opioid 50 times more powerful than heroin, an official close to the investigation told The Associated Press.

The official, who spoke on condition of anonymity because of the ongoing investigation, said records show Prince had no prescription for any controlled substances in the state of Minnesota in the 12 months before he died. Authorities are still investigating how Prince obtained the drugs.

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