Associated Press - November 20, 2009 4:25 PM ET

OMAHA, Neb. (AP) - A fourth person has pleaded guilty to playing some part in the beating death of a west Omaha man or the cover-up attempt earlier this year.

Ryan King pleaded guilty on Friday to a conspiracy charge as part of a deal with prosecutors. In exchange, prosecutors dropped a first-degree murder charge.

Prosecutors have said King, Colton Novoscone and Ryan Carson drove from Mississippi to Omaha to kill 45-year-old Brian Carson last April.

King says that he was there when Carson was killed, but he did not participate.

Prosecutors say Ryan Carson beat his father to death in their family's west Omaha home. Authorities believe an affair Brian Carson had with a woman his son had been dating played a role in the killing.

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