SOUTH PLAINFIELD, N.J. (AP) -- A former New Jersey police chief faces charges for allegedly threatening a boy and shoving his grandmother after an argument at a picnic that started over a water pistol. reports that former South Plainfield police Chief John Muller was charged by a grand jury on Dec. 12 with making terroristic threats and aggravated assault.

Muller's attorney says the case was overcharged and he's mystified that it resulted in an indictment.

The charges stem from an altercation at an Elks picnic on Aug. 30, when authorities say the boy squirted 74-year-old Muller with a water pistol. They say Muller told the boy to stop and grabbed him.

Attorney Joseph Benedict says the boy's grandmother hit Muller in the head with a water bottle and he reacted by pushing her. He says the woman fell and broke her wrist.

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