By Charlie De Mar

NORTH RIVERSIDE, Ill. (CBS) — One person was shot and killed Sunday afternoon on the grounds of the North Riverside Mall.

A police source told CBS 2’s Charlie De Mar the shooting happened in the back of the Olive Garden restaurant at the mall.

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Police were not involved in the shooting, the source said.

Two groups were believed to be shooting at each other, the source said.

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A video clip appeared to show a shooter standing over someone at very close range. Someone was heard firing seven shots.

Evidence markers were set up, and investigators were still working the scene as of 7 p.m.

There were a number of looting incidents at the mall on Sunday.

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A Kohl’s, Burlington Coat Factory, and Petco were targeted, and merchandise was seen strewn around the parking lot.

Charlie De Mar