A Mercer County inmate Wednesday used the jail’s phone to contact the victim of a shooting, trying to deter her from testifying against his “boy” the following day, sheriff’s deputies say.

Kevin Washington, 50, formerly of Sharon and Farrell, called Sylvia Ferguson, 29, of 815 Market Ave., Farrell, and had her patch him through to the victim by three-way call, deputies said in documents.

Washington called on behalf of Antoine Williams, 29, Cleveland, who is charged with attempted homicide for shooting Katrina Austin and Jessica Robinson on May 2 in Farrell and Sharon.

The charges are among several criminal complaints filed by the Mercer County Sheriff’s Department.

Ms. Austin is Ms. Ferguson’s sister, and Williams allegedly chased them after they came to give Ms. Ferguson a ride on May 2. She reportedly had an injury to her face.

Williams stopped his car as Ms. Ferguson got into Ms. Austin’s vehicle. He fired three shots and yelled, “It’s not over till I kill someone,” police said. He chased them, and later fired on them again when they got out of the car. He hit Ms. Austin in her wrist and hip and grazed Ms. Robinson. It was Ms. Austin whom Washington called from jail.

Ms. Ferguson — who referred to Washington as “dad” even though they are not biological relatives, deputies said — patched Washington through to Ms. Austin, and Washington told her to think about not testifying against “his boy,” meaning Williams. It was not clear if Washington and Williams are related.

Washington implied that “nothing good can happen” if she testified against Williams, and that the police would not have a case if she didn’t show, deputies said. He also told her she could benefit financially by not showing up, mentioning financial gain several times.

Ms. Austin told Washington she would think about it, and asked him to call back in an hour. Then she contacted police and filed a report.

Washington and Ms. Ferguson continued to talk after Ms. Austin hung up. Washington asked if Ms. Ferguson thought the other woman bought it, and Ms. Ferguson said she didn’t know, deputies said.

They also talked about a third person, named Loretta, who was allegedly supposed to fund a payoff to Ms. Austin, deputies said.

Washington, who is in the jail on three cases that include drug charges, fighting against police, and bringing contraband — including a cellular phone — into the jail, will now also be charged with intimidation of witnesses and conspiracy, said county information officer Jeff Greenburg.

Williams will be charged with intimidation of witnesses, conspiracy and criminal solicitation, Greenburg said. He is charged with aggravated assault, attempted homicide, reckless endangerment, and terroristic threats for the Farrell incident and is scheduled for a preliminary hearing today before Senior District Judge Henry J. Russo.

Ms. Ferguson is charged with intimidation of witnesses.