CHICAGO (AP) - Chicago police have increased a reward for information leading to the arrest and conviction of all those involved in the slaying of an off-duty officer a year ago.

 

Saturday was the first anniversary of Clifton Lewis' killing.

 

The 41-year-old officer was working as a security guard at a West Side convenience store when he was killed trying to break up a robbery.

 

The reward has been increased from $33,000 to $40,000 thanks to support from the Chicago Police Memorial Foundation and the Fraternal Order of Police.

 

Superintendent Garry McCarthy says he hopes someone will "help us bring closure for Officer Lewis' family and friends."

 

Two West Side men were arrested earlier this year in connection with the killing, but police believe there are others who were also involved.

 

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