A Kansas prisoner who alleged in a lawsuit that he was not being treated properly for cancer has died, his family and attorneys said.

John Keith Calvin, 56, died Wednesday at El Dorado Correctional Facility, where he was imprisoned for a 2002 killing that his attorneys and supporters maintained he did not commit.

In a lawsuit filed last month, Calvin claimed the Kansas Department of Corrections had not provided proper treatment for his colon cancer, The Kansas City Star reported. An emergency filing asking that he be moved to a hospital was denied.

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In a statement, Calvin’s lawyers said his family was "devastated" to share that he died after spending more than 19 years in prison for the Dec. 12, 2002, shooting death of John Coates in Kansas City, Kansas. He would have been eligible for parole in May.

His lawyers at the Midwest Innocence Project and the law firm Morgan Pilate said Calvin was innocent.

"Everyone knew this, and a whole community fought for him," they said. "John Calvin will have a long legacy, and his fight against injustice will continue."

Calvin’s co-defendant, Melvin Lee White Jr., was given a five-year sentence after taking a plea deal in Coates' death. White has said repeatedly in court and interviews that he shot Coates and Calvin was innocent.

Calvin’s case had been referred to the Wyandotte County district attorney’s Conviction Integrity Unit, which investigates complaints of police misconduct and wrongful conviction.

FORMER KANSAS CITY DETECTIVE INDICTED ON CHARGES THAT HE SEXUALLY ABUSED 2 WOMEN

In their lawsuit, Calvin’s lawyers alleged he was "yet another victim" of police corruption in Kansas City, Kansas, "as exemplified" by former detective Roger Golubski.

Golubski has been accused by federal prosecutors and civil rights groups of framing Black citizens and sexually harassing Black women and girls for years in Kansas City, Kansas.

He is currently on house arrest facing two federal indictments alleging he sexually assaulted and kidnapped a woman and a teenager between 1998 and 2002, and that he was part of a sex trafficking ring involving underage girls in Kansas City, Kansas, between 1996 and 1998.

Golubski has pleaded not guilty to all charges.