The untimely death of Craig Mack shocked many fans, but not his close family and friends. In an interview with TMZ, legendary producer Erick Sermon revealed that the former Bad Boy rapper died of congestive heart failure.

The EPMD member said that Mack was only using 25 percent of his heart and had a hard time breathing. Sermon also added that Mack was developing a documentary about his life story and wanted him and several of his New York rap peers like Biz Markie to appear in the project.

Mack's other friend, producer Alvin Toney - who helped sign him to Bad Boy Records - confirmed to New York Daily News that he was working on a documentary before his death.

“Nobody got to understand his story,” Toney told NYDN. “I wanted the world to know the talent he had. It was something I wanted people to enjoy, but it was cut short because he was very religious and wanted to go to church.”

Toney added that Mack knew he was going to die and was preparing for his passing. “He was prepared for whatever comes, to go home to the Lord,” he said. “He was prepared to do that. He wasn’t scared. He was ready.”

Sermon told TMZ that Mack was gravely ill and was in no condition to perform. "He was walking with a cane and he got real slim, but he still had his personality," he said.

"Craig Mack was more of a lyricist, he was a beautiful person," he added. "He had more to say, it's just too bad we didn't get a chance to see it."

Fellow rappers from the hip-hop community also sent condolences to the late rapper's family and friends. You can read some of their tributes here.

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