Social network founder charged with murder

plaxo minh nguyen
David Nguyen, the co-founder of the contact-sharing platform Plaxo, is accused of killing his ex-wife's new husband.

The co-founder of Plaxo, a social network from the pre-Facebook era, has been arrested and charged with first-degree murder for killing his ex-wife's new husband.

Minh Nguyen, 38, is known for helping launch Plaxo, an online address book and platform for quickly sharing and synchronizing contact details. The company was bought by Comcast (CMCSA) in 2008.

He was arrested Thursday night in Ashburn, Va., a suburb of Washington. Police there say he entered his ex-wife's home and shot Corey Mattison, the man she had just married. Two of Nguyen's children were in the townhouse at the time. Nguyen's ex-wife Denise was with their third child when she walked in on the gruesome scene.

None of the others in the home were hurt, according to Loudon County Sheriff's Office. Police arrested Nguyen without any resistance.

Nguyen's ex-wife, Denise, had just remarried in November, according to public notices online. Mattison was a project manager at a glass construction company in the Washington area.

Mattison's colleagues at the small company, who had gotten to know him well over the last eight years, said they were devastated by his death. They described Mattison as a calm listener who spent most of his weekends caring for all the children in his life. He had two elementary-school-aged children from a previous marriage and spent much of his time with his new wife Denise's three children as well.

"Corey was a great guy," said Rick Knutson, the firm's owner. "He was someone we could depend on. He's the kind of person you just can't replace."

Kuntson also said Mattison had privately voiced concerns over Nguyen's incessant interruptions during weekends with the kids.

"Corey and his wife would go to a baseball game with the kids, and [Nguyen] would blow up," Knutson said. "He would try to prevent them from taking the kids anywhere. The guy seemed to be a little unstable."

Nguyen is being held at the Loudon County Adult Detention Center without the option to be released on bond.

Since Plaxo was sold to Comcast, Nguyen had remained an active entrepreneur in San Francisco. He served as an adviser to several startups and regularly attended talks on robotics.

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