Teen Tech Whiz Arrested in House Party Shooting: Cops

A teenage house party outside Seattle turned deadly early Saturday after a gunman killed several of the estimated 15-20 young partygoers.

A teenage house party turned to tragedy early Saturday when three partygoers were shot dead and a fourth injured outside Seattle.

Allen Ivanov, 19, was arrested in the ensuing hours as cops say he sped down a freeway many miles from the grisly scene in the affluent suburb of Mukilteo, Washington.

Ivanov, described by his peers as a tech whiz who started his own laser tag company as a young boy, posted cryptic messages to social media in the days and hours leading up to the shooting.

“First and last tweet. I’ve been through it all,” the teen tweeted on Thursday, before breaking his word and writing a second tweet that read "What's Ruger gonna think?"

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While it is not clear if Ivanov was referring to the gun company in his tweet, the message in an Instagram photo he posted Monday is now clear. It shows a rifle and three cartridges laid out on what looks like the front steps of a home.

Police say around 15 to 20 young people were in the home when the suspect walked in and open fire sometime after midnight.

Police did not identify victims, but early reports appeared to indicate the fourth victim had at least a fighting chance of survival.

The suspect was known to some people at the the party. According to the Seattle Times, he is the ex boyfriend of one of the victims.

At least some parents were informed of the shooting via text messages they received from children who witnessed it.

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Before sunrise, Mukilteo police announced they'd apprehended a suspect miles to the south in Lewis County, accoridng to KONG.

Authorities announced at an early morning press conference that they were not seeking any additional suspects.

Mukilteo Mayor Jennifer Gregerson also addressed the press. "We grieve with the families who have lost those in this horrible event," she told reporters early Saturday.

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