A grand jury has indicted a teen on first- and second-degree murder charges, as well as manslaughter and multiple counts of assault.

Palmer Assistant District Attorney Rick Allen confirmed the update in the case against 19-year-old Jordan Flowers, who is suspected of shooting and killing Gunnar Swan, also 19, on Jan. 27. Court documents from earlier this week detailed witness accounts, what investigators found on the scene, and what troopers learned while interviewing Flowers.

When he appeared in court on Monday, Flowers was arraigned for one count of manslaughter and three counts of third-degree assault. Allen said then that he felt the charges would change.

"We received some additional information since the affidavit was filed and it's very, very likely this is going to be going to murder from manslaughter," he said that day.

Judge Craig Condie set Flowers' bail at $100,000.

Allen said he couldn't comment on additional evidence uncovered in the investigation, but said later court filings will illuminate why the state made the decision to upgrade Flowers' charges.

Flowers will likely be arraigned on the new charges next week.

Heather Hintze contributed to this report.

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