The investigation surrounding Prince's death continues.

The District Court of Carver County in Minnesota has issued an order to seal all findings from a recently-issued search warrant into Prince's Paisley Park Studios, where the 57-year-old superstar died last week. The results will be unsealed following any criminal proceedings or 180 days from the April 28 filing, whichever occurs first.

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Meanwhile, an eyewitness tells ET that a locksmith was spotted at Paisley Park on Wednesday. According to local media in Minneapolis, Minnesota, the locksmith was hired by Bremer Bank, the recently appointed special administrator of Prince's estate, to drill into the singer's secret vault.

A source tells ET that the vault, which contains "hours upon hours" of original recordings on cassette tapes, is roughly the size of a utility closet and was secured with about five heavy locks.

Upon reaching out for further details, Bremer Bank told ET "it respects the privacy of our customers and it is our policy not to reveal the names of our customers or information related to requests for services. As a community focused company, our sympathies are with family and fans in mourning the loss of a talented musician and Minnesotan."

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Prince was discovered unresponsive in an elevator on his Paisley Park estate in Chanhassen, Minnesota, on April 21.

On Wednesday, a law enforcement source told CBS News that prescription drugs were found in Prince's possession and at his home at the time of his death.

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Prince's body was cremated last week following an autopsy, which included a toxicology report. He was laid to rest by his closest family and friends with a private memorial on Saturday.

"A few hours ago, Prince was celebrated by a small group of his most beloved: family, friends and his musicians, in a private, beautiful ceremony to say a loving goodbye," the statement from his publicist read. "Prince’s remains have been cremated and their final storage will remain private. We ask for your blessings and prayers of comfort for his family and close friends at this time."

"The cause of death remains unknown and it will be at least four weeks before we receive the results of the autopsy," the rep added. "An announcement will be made at a future date for a musical celebration."

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