Throughout his life and career, Prince Rogers Nelson pretty much maintained a clean and healthy lifestyle. Compared to many of his contemporaries who fell victim to alcohol and substance abuse, the pop superstar deliberately tried to stay away from things that could get in the way of his work.

However, as more details about Prince's death are beginning to be uncovered, it appears that he kept his battle with painkiller pill addiction a secret even to his closest friends.

Just before Prince passed away, his friends had arranged for him to receive medical help from pill addiction specialist Dr. Howard Kornfeld, but the intervention may have come too late for the music icon.

According to Kornfeld's lawyer, William J. Mauzy, the doctor had sent his son Andrew to meet Prince at his Minnesota home in order to talk about his treatment plan. Andrew was one of those who found the musician lifeless in the elevator, and he promptly called 911.

Emergency responders tried to revive Prince but ultimately weren't able to do so. He died at the age of 57.

While investigators are still in the middle of finding more information about Prince's death, there is growing evidence that suggest he had indeed developed a serious addiction to painkiller medication, something that contradicts what people knew about the pop superstar.

Many of those close to Prince have even insisted in recent days that they never saw him take any pills, particularly prescription medication. Some of them, however, were aware that he underwent hip surgery a few years ago.

Prince's friends became even more worried about his health when he was rushed to a hospital in April after becoming unresponsive during a flight. Prince told his friends that he was all right following the incident. His publicist said that the musician only had the flu.

Mauzy said that on the morning when Prince was found dead, Kornfeld called a colleague in the Minneapolis area to have him check up on the musician so that they can assess his status. He pointed out that Kornfeld's plan was to stabilize Prince's health and convince him to seek further medical help at the doctor's treatment center in California.

Mauzy added that Kornfeld treated it as a lifesaving mission.

A person who knew Prince but had requested to stay anonymous revealed that the pop superstar had been taking pain medication for his ailment for several years until he finally decided to get hip surgery a few years back. He said that Prince was prescribed to take more painkillers following the operation.

Chief Deputy Jason Kamerud from the Carver County Sheriff's Office said that investigators assigned to the case are already looking into the likelihood that Prince had overdosed on painkillers, among other possible reasons of his death. Kamerud, however, declined to comment on the statements provided by Kornfeld's legal counsel.

The sheriff's office said it did not believe that murder or suicide was the cause of the pop superstar's death.

The U.S. Attorney's Office and the Drug Enforcement Administration (DEA) said that they were also joining the investigation.