After going more than a year with no arrests, the wife of a Milwaukee man killed in 2017 has offered a $200,000 reward for information leading to an arrest.

The murder happened in December 2017 during a convenience store robbery. Ala Mahmoud, 40, was shot and killed by the unidentified robber.

Police have yet to identify a suspect.

Not long after his death, Mahmoud’s wife Katherine Mahmoud announced a $50,000 reward courtesy of herself and the family for information leading to an arrest.

"Bring me someone who can run it down and lead to the shooter, and it’s yours. ... I’m not stopping, I’m not going away," Katherine Mahmoud told NBC affiliate WTMJ, after raising the reward money from $50,000 to $200,000 for information leading to an arrest.

Along with his wife, Ala Mahmoud left behind an 18-year-old daughter and an 8-year-old son, while Katherine Mahmoud was pregnant. The couple had been married 21 years.

In December 2017, Katherine Mahmoud said that "somebody is going to recognize that figure [in the surveillance video] even if they had a mask on. He will be caught."

WTMJ noted that the Milwaukee Police Department success rate with murder cases, with 67% solved in 2016, 78% in 2017 and 76% in 2018.

The Milwaukee Police Department has not commented on the recent increase in the reward but WTMJ quoted Reggie Moore, of Milwaukee's Office of Violence Prevention.

"Unfortunately no amount of money can replace the life that was taken, but again, I think it underscores the impact of how important justice is when we talk about healing," Moore said.

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