BRIDGEWATER — A 27-year-old man was arrested after a police standoff Monday night and charged with killing a woman and stabbing his father in their home.

Police arrived at the home on Washington Valley Road in the Martinsville section of the township around 8:20 p.m. to find Michael Litwornia barricaded inside and his 61-year-old father outside on the front lawn with serious stab wounds.

Somerset County Prosecutor Michael Robertson on Tuesday said police used a robot to find Litwornia lying on a couch with self-inflicted wounds.

Inside the home, police found the woman, later identified by Robertson as Litwornia's mother Helen, with serious stab wounds to the neck.. She was pronounced dead after police took her from the house.

Police did not identify Litowornia's father by name. Property records identify the owners of the home as Stephen and Helen Litwornia.

Around 11 p.m., the SWAT team broke into the house and took Litwornia into custody. Police said he attempted to grab a "sharp force instrument" before they subdued him.

Litwornia refused to speak with police.

He was been charged with first-degree homicide and second-degree aggravated assault and will be taken to the Somerset County Jail pending a detention hearing.

Neighboring residences were evacuated as the Somerset County SWAT team was brought in and surrounded the house.

Robertson said an investigation continues into a motive for the attacks.

Robertson asked anyone with information about the incident should call the Somerset County Prosecutors Office Major Crimes Unit at 908-231-7100 or the Bridgewater Township Police Department at 908-722-4111.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com.

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