Rochester, MN (KROC-AM News)  A Rochester teenager was arrested Tuesday night after police say he assaulted two younger teens and an adult who came to their assistance.

Captain John Sherwin says the incident happened in the ballpark area of Quarry Hill Park around 7 p.m. Sherwin says the 17 year old confronted the two 14 year old boys and began fighting with them.

A 40 year old man tried to stop the assault and was punched in the face. The man told police the teen also threatened him with a knife or brass knuckles. The man went to St. Mary’s to be checked out after becoming dizzy.

The teen fled but officers located him a short while later and took him into custody.

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