MINNEAPOLIS – A Minnesota doctor questioned by investigators in Prince’s death is an experienced family care physician who worked for a Twin Cities health care system until recently.

A search warrant revealed Tuesday that Dr. Michael Todd Schulenberg, 46, treated Prince on April 7 and April 20 and prescribed him medications, though it didn’t specify which or say whether Prince took them. Prince was found dead April 21 in his suburban Minneapolis home.

A law enforcement official has told The Associated Press that investigators are looking into whether Prince died from an overdose and whether a doctor was prescribing him drugs in the weeks before his death. The law enforcement official has been briefed on the investigation and spoke to the AP on condition of anonymity because he was not authorized to speak to the media.

Investigators interviewed Schulenberg and searched a suburban Minneapolis hospital where he worked. The warrant did not specify what medications were prescribed or whether Prince took them.

Schulenberg was a primary care physician for North Memorial Medical Center until at least April 21, but he has since left the job. Lesa Bader, a spokeswoman for the health care system, said personnel records are private and she couldn’t comment on why Schulenberg no longer works at their Minnetonka clinic.

No one answered the door at the doctor’s home on Tuesday and phone messages left for him weren’t returned.

Schulenberg earned his MBA in health care recently from the University of St. Thomas in St. Paul. In a 2012 YouTube video posted by the university, Schulenberg said he was then part of the “leadership group” at Ridgeview Medical Center in Carver County and said his job required him to put in demanding hours.

“As a full-time family physician, that probably demands about 50 hours a week,” he said in the video. “I still deliver babies, so I can be called in on an unexpected basis and there goes my evening.” Schulenberg described himself in the video as a father of five.

Lisa Steinbauer, a spokeswoman for Ridgeview, said Schulenberg left the health care system in August of 2014.