Portland police arrested seven teenagers on Tuesday following an assault at a Southeast Portland MAX station that left one man injured. But many of the teens were also suspects in a slew of crimes at TriMet stations last month, police said.

Around 2 p.m., police responded to the Holgate Boulevard Transit Station for reports of a threat involving a weapon. They found a man who had been assaulted and had non-life-threatening injuries. Officers found the suspects had flashed a knife, but didn’t use it in the assault. The teens fled, but officers used police dogs and arrested the suspects a short while later.

Police arrested six boys, ranging from ages 13 to 16 and one girl, age 13.

Police said they had reviewed video footage and identified suspects based on incidents at four other transit stations: on Feb. 11 at the 7th Avenue station, Feb. 16 at the 82nd Avenue station, Feb. 20 at the 162nd Avenue station and Feb. 21 at the Lloyd Center station. Two teens were arrested at the most recent incident, and were not involved with Tuesday’s assault.

With the exception of two boys, all the teens face charges related to incidents prior to Tuesday’s. The teens were charged with a series of crimes based on the Tuesday encounter including robbery, assault, riot and interfering with public transit. The previous cases include similar charges.

Police did not immediately say what the teens had stolen from victims, nor the exact manner in which they robbed them.

Police said they think there may have been similar incidents on TriMet property, and have asked potential victims to come forward.

The teens have all been lodged at the Donald E. Long Juvenile Detention Center.

—Jayati Ramakrishnan; 503-221-4320; jramakrishnan@oregonian.com; @JRamakrishnanOR

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