A central New Jersey man and his mother face murder charges in the beating death of one of the man's acquaintances.

Bail has been set at $2 million each for 37-year-old James Thomas and 53-year-old Shelley Thomas, both of Plainfield. Their arrests were announced Monday by Middlesex County Prosecutor Bruce Kaplan.

The two are charged in the death of 53-year-old William Koonz Jr., who was found dead Friday in his South Plainfield home after concerned relatives asked police to go there and check on him.

An autopsy determined Koonz died from blunt trauma to the head.

Kaplan said the attack was not a random incident, but declined to provide further details. He said a motive has not been determined.

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