PORTLAND, Ore. (AP) – Portland police are investigating whether the man charged with killing two men and wounding another on a light-rail train stabbed a man in the back earlier this year.

Portland police Sgt. Chris Burley said Friday that 35-year-old Jeremy Christian is "a main suspect" in the stabbing that happened Jan. 27 outside Voodoo Doughnut in downtown Portland.

Burley says the investigators are not releasing additional information about the case

The stabbing occurred on the morning of Jan. 27 during a fight outside the popular doughnut shop. The victim ran into the shop asking for help before being taken to the hospital.

Christian has been in jail since May 26, when police say he stabbed three train passengers after going into an anti-Muslim tirade. He pleaded not guilty to aggravated murder and other charges.

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