By CBSLA Staff

LONG BEACH (CBSLA) – An ex-con pleaded not guilty Wednesday to charges stemming from the shooting death of a 50-year-old man at a park in Long Beach last September.

Michael Scott Doss Jr., 21, of Long Beach, is charged with murder for the Sept. 25 slaying of Long Beach resident Richard Winfrey, 50, who was killed at a park in the 800 block of East Seventh Street.

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Doss is also charged with one count each of attempted murder; possession of a firearm by a felon and unlawful possession of ammunition, according to the Los Angeles County District Attorney’s Office.

Doss was in custody on unrelated charges when he was arrested last month in connection with the shooting, which detectives believe stemmed from a dispute that escalated, according to Long Beach police.

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Co-defendant Christian Lucille Watson, 30, of Carson, pleaded not guilty to one count each of being an accessory after the fact, possession of a firearm by a felon and unlawful possession of ammunition.

The two are also facing charges in a separate case, in which Doss is charged with second-degree robbery, assault with a firearm, and possession of a firearm by a felon, and Watson is charged with second-degree robbery, according to the District Attorney’s Office.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)