Prince, photographed at the 2015 American Music Awards in Los Angeles, Nov. 22, 2015, became addicted to painkillers nearly a decade ago, friends said. Getty Images

Very little is known yet about Prince’s cause of death, but that hasn’t stopped rumors from circulating. With an investigation into the music legend's death ongoing, fans have been forced to draw their own conclusions, with many leaning toward a possible overdose.

While Prince’s lawyer maintains the pop icon lived a clean, healthy lifestyle, his close friends say he was battling a secret addiction to Percocet. In an interview with Us Weekly, one friend, Sky Dangcil, said Prince’s use of Percocet, a combination of acetaminophen and oxycodone, traced back nearly a decade to a time when he injured his hip. He is said to have used the pills to “keep the show going.” Dangcil, who played music alongside Prince, 57, for seven years ending in 2007, claimed the “Purple Rain” singer was in a constant state of aching, though he would never admit it.

“He was always ‘on,’ so he wouldn’t complain or say anything was wrong,” Dangcil revealed.

Another friend, Kim Berry, who did Prince’s hair, told Us a similar tale. She speculated the singer's many sleepless nights working on music and his nearly three decades “jumping off speakers with 4-inch shoes on” likely contributed to his aches and pains. Berry told Us that Prince refused to let his pain slow him down, furthering his addiction.

While fans await the announcement of Prince’s official cause of death, allowing them some closure, authorities in Minnesota — from where the iconic musician hailed — are searching for answers from doctor Michael Todd Schulenberg. Prince reportedly met with the physician, who'd written him several prescriptions in the past, in the days leading up to his death, on April 21. TMZ reported police obtained a warrant to examine the singer’s medical records Tuesday after learning Schulenberg had been prescribing painkillers to the singer.

Prince is said to have filled four prescriptions at a local Walgreens in the week leading up to his death. It remains unclear whether the prescriptions were written by Schulenberg or, as TMZ suggested April 29, the singer had been shopping around for other doctors. Percocet is a controlled substance, which would mean the singer could not legally obtain four full prescriptions for the drug to which he is said to have been addicted. There is also some speculation Prince may have used aliases to obtain the prescriptions. Those reports are, however, unconfirmed.

The Midwest Medical Examiner’s Office in Ramsey, Minnesota, has yet to make Prince’s cause of death public. It did release a statement May 5, though it provided few details about his passing. The office assured fans no cause of death would be released until officials were absolutely certain, adding the investigation into Prince’s death was still “ongoing.”