(CNN) The wife, child, and mother-in-law of a pitcher in the Tampa Bay Rays organization were killed in a southern Virginia town Tuesday, and police arrested the brother-in-law of minor league baseball player Blake Bivens, authorities said.

Matthew Thomas Bernard, 18, was arrested on three counts of first-degree murder, a spokesperson for Pittsylvania County, Virginia, said in a statement provided to CNN.

The victims were identified Wednesday as Joan Denise Jefferson Bernard, 62; Emily Bernard Bivens, 25; and 14-month-old Cullen Micah Bivens, according to Pittsylvania County Sheriff Michael Taylor. They were the mother, sister and nephew of the suspect, he said.

Taylor confirmed the victims' relationship to Blake Bivens. He said authorities waited for the player to returned to Virginia before releasing the names.

A 911 call around 8 a.m. Tuesday morning reported that a person had been shot, the spokesperson said. Deputies went to the scene where they found a deceased woman in the driveway and the bodies of another woman and a child inside the home.

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