A 20-year-old accused of robbing a man at knifepoint along a Northeast Portland MAX train platform was arraigned in Multnomah County Circuit Court Wednesday.

Dylan Scott Allen was arrested on an allegation of first-degree robbery Tuesday.

Dylan Scott Allen

According to a probable cause affidavit filed in court, the victim was working on his laptop computer while riding on the train. When he got off at Northeast 60th Avenue, he said a few people followed him out.

The man with the computer was walking up stairs from the MAX platform when he said Allen armed with a knife threatened to cut his throat and demanded he turn over his bag to him, the affidavit said.

The two men struggled over the victim's bag. Allen fled without getting the bag or any of its contents.

Witnesses identified Allen as the robbery suspect, and police reviewed video surveillance images, leading to Allen's arrest, the affidavit said.

Allen "cried profusely'' and told police that his female companion was the "mastermind'' of the robbery. He also started to write an apology letter but didn't finish it, the affidavit said.

--Maxine Bernstein