CHICAGO (CBS) — Newly-released surveillance video showed people running and ducking for cover during a shooting along the Chicago River downtown last weekend.

Police released the video Wednesday in hopes of identifying possible witnesses or suspects.

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Investigators are zeroing in on two men who are seen on the video possibly holding guns.

One woman and one man were killed in the shooting early Sunday morning.

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They were found in a car in the 0-99 block of East Wacker Drive near Wabash Avenue around 2:30 a.m. Sunday when they waved down officers for help, according to Chicago Police.

Police said a quarrel between an unidentified man and a group of people led to that same man taking out his gun.

“‘Boom! Boom! Boom!’” said witness Travis Whitaker. “Next thing you know, shorty’s laying there.”

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The 35-year-old man was shot once in the neck, and the 25-year-old woman was shot once in each arm. Both were taken to Northwestern Memorial Hospital, and the man died a short time later. The woman was reported in good condition.