Someone at Prince’s Paisley Park estate in Minnesota dialed 911 for medical help four times since 2013. One call was placed on Oct, 23, 2013, another was placed on Aug. 9, 2015 and another just weeks later on Sept. 23, 2015. The last call was placed on April 21, 2016 when Prince died.  

Units were dispatched to the home on Oct. 23, 2013 and Aug. 9, 2015 but not for the September 2015 call, documents from the Carver County Sherriff’s Office reveal.

The outcome of the three calls is not public information. FOX411 has requested reports from the three medical dispatches.

Prince was found on April 21st in the elevator of his Paisley Park estate in Chanhassen, Minn.

Meanwhile, a Minnesota judge has sealed a search warrant in the investigation of Prince's death after authorities argued that making it public would hamper their work.

The search warrant is for Paisley Park. The local sheriff and prosecutor filed papers Thursday requesting it be sealed. They cited the intense media scrutiny following Prince's death.

Deputies and medical personnel found the 57-year-old music icon unresponsive when they arrived at his home, and they performed CPR but it was unsuccessful. He was pronounced dead at 10:07 a.m. local time.

The singer's death came six days after he was rushed to an Illinois hospital after falling ill while returning to Minneapolis from a concert in Atlanta.

An autopsy was completed last week on the body of the seven-time Grammy winner but the results have not been made public. The results of a “full toxicology scan could likely take weeks,” the Midwest Medical Examiner’s Office told FOX411 last week.

Fox News' Leora Arnowitz and The Associated Press contributed to this report.