The Carver County Sheriff’s Office and several other detectives have revisited Prince’s Paisley Park estate as part of their ongoing investigation.

On Tuesday evening, the Carver County Sheriff’s Office tweeted that the search was merely part of a “complete” investigation.

According to the Minneapolis Star-Tribune , investigators are looking into whether Prince died on April 21 from a drug overdose and if he had obtained medication from a doctor.

A search warrant – which has since been sealed – and police affidavit found that Dr. Michael T. Schulenberg, who practices family medicine, saw Prince on April 7, the day he canceled his first scheduled concerts in Atlanta , and again the day before he died.

According to The New York Times , on the morning of Prince's death, Dr. Schulenberg had arrived at the musician's compound to discover he had just been pronounced dead.

The affidavit stated that Dr. Schulenberg had performed tests and prescribed medication for an undisclosed ailment during Prince’s two visits and went to his home on April 21 to present him with the test results.

Dr. Schulenberg, 46, has been licensed to practice in Minnesota since 1997. He has no disciplinary history, according to state records, and there are no allegations of wrongdoing on his part. The warrant sought medical records from the North Memorial Medical Center, which is part of the health system where Dr. Schulenberg used to work.

As previously reported , Prince's team had reached out to Dr. Howard Kornfeld a national authority on opioid addiction based in California.

Dr. Kornfeld wasn’t able to rush to Minneapolis April 21, but planned to fly out the following day and instead sent his son, Andrew Kornfeld, who works with him, to the Paisley Park compound to evaluate the singer’s health and devise a treatment plan.

Andrew Kornfeld arrived at Prince’s estate around 9:30 a.m. April 21 after taking a red-eye flight from San Francisco; he and two of Prince’s representatives found the musician unresponsive in an elevator. Andrew Kornfeld was also the person who called 911.

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