We begin tonight with breaking news. After an urgent search, 34-year-old man who police believe murdered a wealthy Washington, D.C. Couple, their young son and their housekeeper is now in custody.... See More
We begin tonight with breaking news. After an urgent search, 34-year-old man who police believe murdered a wealthy Washington, D.C. Couple, their young son and their housekeeper is now in custody. ABC's Ryan smith has exclusive new details. Reporter: Breaking news tonight a frantic interstate manhunt ends with this man, Daron dylon Wint in custody. A long 48 hours and it was a collaborative effort of a lot of different agencies, all of them part of our task force. Reporter: The suspect in that brutal quadruple homicide at this Washington, D.C. Mansion charged with murder in connection with the deaths of savvas savopoulos his wife Amy, their 10-year-old son Phillip and their housekeeper veralicia Figueroa. When captured in a vehicle after a police chase. We continued to follow him. We called P.G. County police and they sent up a helicopter. We got to a situation where we could successfully take him down and we were able to safely pin the vehicles, both vehicles and place him under arrest. Reporter: He was considered armed and dangerous. Relatives describe Wint as an angry, troubled man. Very hostile, arrogant. He doesn't listen. Reporter: Wint has a long rap sheet with arrests for burglary, assault and concealing a dangerous weapon. That criminal history led to his identification. Police say they tracked him down from DNA on a crust of domino's pizza, ordered to the savopoulos house while they were held hostage. Just about every law enforcement officer across the country that is aware of his open warrant are looking for him. Reporter: Now police say Wint was no stranger to the slain family and their business. This is American iron works, a steel and iron manufacturer. Savvas savopoulos was the CEO and police say Daron dylon Wint worked for the company at some point and that's the connection between the two. Employees there still in a state of shock. How's the company holding up? Not good. Reporter: Not good. If the husband knew who he was all four could identify him at some point. To eliminate the witnesses you kill all of them. Reporter: The family's ordeal began last Wednesday evening. I hope you get this message. Reporter: The employee receives a message instructing her not to come to work the next day. Amy is in bed sick tonight and she was sick this afternoon. Vera offered to stay and help her out. So she's going to stay the night here. Vera's phone died and doesn't have her charger and I don't have a charger that fits her phone. I don't know if you can tell anybody that would be worried about her that she is just going to be here with us tonight. We know this voice mail is all wrong. If you listen to it, he has a very flat affect. If this were a casual call, it would be along the lines of, hi, remember we don't need you tomorrow. Everything's fine. I'll see you on Monday, click. It was a slow, methodical, flat affect call and if you listen very carefully, you can hear some sort of commotion in the background. Reporter: That same night, two domino's pizzas are ordered and left on the doorstep of the home. We were contacted by the police the day after. We can confirm we made a delivery to the house. Reporter: The next morning starting at 7 A.M., savopoulos made a flurry of calls. Some to his bank and an accountant. That morning an assistant of savopoulos dropped $40,000 off at the house. A few hours after the money is dropped off, the house is up in flames. 3201 woodland drive, three story house fire on second floor. We removed four victims. It's going to be a prolonged secondary search. This case sort of wreaks of amateur behavior. Fwhapd that house? What motivated the bad guy or bad guys to harm these people in such a horrific way? That remains to be seen. Reporter: Police information suggest that savvas savopoulos, Amy and Vera were doused with gasoline and stabbed to death. While 10-year-old Phillip was found in his room, burned beyond recognition. The family's car was found on fire in this church parking lot, 15 miles away. This surveillance video, the first clue as to who committed this horrific crime but it was here at the ATF specialized lab in more THR that police say they got their tloing Daron dylon Wint. Every piece of evidence taken from that scene was sent to our lab. Our lab worked around the clock on the evidence received from there. Reporter: Authorities say the lab matched trace DNA evidence from the domino's pizza to Wint. The investigation is still ongoing but we have ruled out whether there was or wasn't participation from other people involved in this thing. This crime would be difficult to pull off with one person. You are talking about controlling people for a full 24-hour period and the idea that one person could do that, possible, of course. The ten din deny is I think there would be more than one person. Reporter: Police tracked down Wint's girlfriend in this home. Wint was still at large earlier this evening. Police interviewed Wint's girlfriend at this police station earlier today. They say she was cooperative. Reporter: Wint was a one-time marine recruit who grew up in Guyana. His girlfriend told police she believed he would turn himself in. Before Wint was taken in to custody, the savopoulos D.C. Community was on edge. What do you say to members of the general public who maybe concerned he may come after others? Right now I think we have established there is some specific connection between the suspect and the victims here. So this was not random. We -- hopefully will have Mr. Wint in our custody very soon. Right now everybody in the neighborhood shaken up. They are not sure what to think. Reporter: The savopoulos have two surviving daughters who were away at boarding school at the time of the killings. Police have their families' alleged killer in custody. Tonight we were able to find the location of Wint and take him down and arrest him. Reporter: For "Nightline," I'm Ryan smith in Washington, D.C.
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