Police received 47 calls from Prince's Paisley Park residence over the past five years, with three in the past nine months alone for unspecified medical emergencies, the last of which was on his death.
A police report containing details of the response to his death including how emergency services battled to save him has now been released, with officers indicating they have launched a "criminal" probe.
The 57-year-old superstar was found "unresponsive" in an elevator at his $10 million Paisley Park estate in Minnesota last Thursday.
Documents have now confirmed details about the incident and show the singer was pronounced dead less than 20 minutes after an ambulance arrived on the scene shortly before 9.50am.
Jason Kamerud, chief deputy of Carver County Sheriff's Office, wrote: "On 4/21/2016 at about 0943 hours, sheriff's deputies were dispatched to a medical call at Paisley Park.