WATCH: Slaying of man, family probed as brother charged with arson

WATCH: Slaying of man, family probed as brother charged with arson

Transcript for Slaying of man, family probed as brother charged with arson

Chilling new details in the mansion deaths in New Jersey. Prosecutors revealing how a father, mother and their two children were killed, their house then set on fire. The father’s brother now under arrest, and accused of torching his own home. Here’s ABC’s gio Benitez. Reporter: Tonight, authorities in New Jersey say a nightmare unfolded inside this burning mansion. The killing of an entire family followed by arson. This is one of most heinous cases that I think they have ever investigated, that we have ever seen. Reporter: Police recovering the body of 50-year-old Keith caneiro Tuesday outside his home with multiple gunshot wounds. All units operating, 15 willow brook road, colts neck. Every vac wait the building. Reporter: Inside, the bodies of his wife Jennifer, and who they believe to be their two children. A source telling ABC news investigators suspect all three were stabbed. Unfortunately, sadly, each of these individuals were the victims of homicidal violence at some point prior to when fire was set. Reporter: It turns out, earlier in the day, ten miles away, the home of the victim’s brother was also burning. Today, police charging that brother, Paul caneiro, with aggravated arson of his own home, saying, “He doused it with gasoline, then set it on fire while his wife and two daughters were inside.” No one was injured. Police say the two fires are related, but they have not called caneiro a suspect in the death of his brother and family. The two brothers ran a tech company together. The victim, Keith caneiro, was the CEO. And gio Benitez joins us live tonight from colts neck, new Jersey, where that family was killed. Gio, so many questions in this case. That brother will be in court next week? Reporter: He will, Tom. He’s facing those arson charges. Meanwhile, police here say that there is no threat to public safety. They call what happened to that family a targeted attack. Tom? Gio Benitez. Thank you. We turn to politics now. President trump interrupted

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