WILLINGBORO, N.J. (CBS) — Authorities in Burlington County have indicted a 23-year-old Willingboro man in the murder of his ex-girlfriend’s grandmother and brother. Terrance Matthews is facing two counts of first-degree murder.

On June 20, authorities say Matthews killed 9-year-old Ishon Mathlin Jr. and 68-year-old Jennifer Vasell. Prosecutors say both were stabbed multiple times and Ishon had been drowned in a bathtub.

The murders happened inside the Eastbrook Lane home the suspect shared with the victims.

Police say Matthews has also been charged with the February killing of a man who was sitting in a car in Willingboro.

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Investigators say Matthews murdered the victims while his ex-girlfriend was at work and when she returned, he held her hostage throughout the night. The next day, his ex-girlfriend told a Wawa employee that Matthews had killed her family and he fled the store.

Matthew then led police on a high-speed chase while live-streaming the pursuit on Facebook before he crashed into a pole and was taken into custody.