A man who died Friday after being robbed and beaten at a Capitol Hill convenience store had lost his 25-year-old son to violence four years ago during a fight in a prison where he was serving time for bank robbery.

Carlton Coltrane, 60, was attacked about 12:30 a.m. May 6 at the 7-Eleven in the 400 block of Eighth Street SE. It occurred at the north end of the Barracks Row strip of restaurants and bars, two blocks from the Eastern market Metro station.

Coltrane, of Southeast, died Friday, and the medical examiner ruled the death a homicide over the weekend. D.C. police have put out a video of two men they want to question. They said the attack started inside the store and continued outside.

In January 2010, Coltrane’s son, Carlton Rama Coltrane, 25, was fatally stabbed in a federal prison in Pollock, La. An FBI spokeswoman in New Orleans, which is handling the investigation, said it was determined the other man acted in self defense.

On Monday, Mary L. Coltrane said she is devastated by the news of her ex-husband’s death. “It’s very heartbreaking,” she said. “I’ve lost both of them tragically. It’s very hard.”

Mary Coltrane declined to comment further, saying police had asked her not to discuss the case due to their investigation.

The younger Coltrane was convicted in U.S. District Court in Alexandria in July 2008 on one count each of armed bank robbery, using a firearm during a crime of violence and conspiracy. He had been scheduled to be released in 2018.

D.C. police are offering a reward up to $25,000 to anyone providing information that leads to the arrest and conviction in the elder Coltrane’s death. Anyone with information is urged to call police at 202-727-9099.

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