A petition signed by over 6,000 Prince fans are asking the U.S. attorney for Minnesota to convene a grand jury to investigate the singer’s death.

Prince, whose legal name was Prince Rogers Nelson, died of an accidental fentanyl overdose in 2016 after taking counterfeit Vicodin pills laced with fentanyl.

One of the 57-year-old singer’s fans who helped organize the petition, Nicole Welage, says the group went through 214 pages of investigative documents and the transcript of the 911 call to authorities after Prince was found in his Paisley Park home.

”He led a clean life, and he’s being completely painted as a drug overdose — another Elvis.”

Meanwhile, six of Prince’s siblings have filed a wrongful death lawsuit accusing a doctor and several healthcare services of failing to diagnose and treat his opioid addiction and prevent his death.