Convicted reputed mobster Frank Calabrese Sr. has died, authorities said Wednesday.
Calabrese Sr., 75, who was sentenced to life in prison in January 2009 after being convicted in Chicago's biggest mob trial in decades, died Tuesday in a North Carolina prison.
No cause of death has been determined, but Calabrese suffered from several ailments, including heart disease, the Chicago Sun-Times reported.
His son, Frank Calabrese Jr. -- who risked his life and secretly recorded his father in prison as he bragged about mob murders -- said Wednesday he had "a lot of emotions" running through him.
"It’s very emotional right now because there were two sides to my dad, and I miss the good side," said Calabrese Jr., a key witness against his father at trial.
"I believe he was taken on Christmas Day for a reason," Calabrese Jr. said. "I hope he made peace. I hope he’s up above looking down on us."
The court held Calabrese responsible for more than a dozen killings. To pay the ordered restitution of more than $4 million to the families of his victims, the feds searched Calabrese's Oak Brook home in 2010 and found hundreds of thousands of stashed jewelry and cash behind a family portrait.
The items were auctioned this year.
In September, the writer of "Goodfellas" signed on to tell the story of Calabrese and his son, who turned away from mob life and secretly helped the feds record his father's conversations.
"He’s not suffering any more. The people on the street aren’t suffering any more," Calabrese Jr. said.