IOWA CITY, Iowa (AP) -

Federal prosecutors are taking over the case against two drug-dealing suspects who were linked to an undercover sting in which a state agent killed one of their associates in Iowa City.

A federal indictment returned last week charges John Mulbah and Norman Dudley with conspiracy to distribute cocaine base. Prosecutors in Johnson County filed motions on Monday to dismiss similar state charges against Mulbah and Dudley.

Mulbah pleaded not guilty Monday in his initial federal court appearance.

The men were arrested in August after an undercover Iowa Division of Narcotics Enforcement action at an Iowa City trailer park.

An agent who went to buy drugs undercover had a gun pointed at his head by Ivan Hardemon, but managed to break loose and fatally shoot Hardemon and injure DeMarco Dudley.