PORTLAND -- A swim instructor from Beaverton was arrested by police for sexually abusing young girls in a secluded room at the Sunset Athletic Club.

Mitchell Alan Douglas Kelly, 17, was arrested after the facility reported the abuse to police on June 23, according to the Washington County Sheriff's Office.

Kelly was arrested and arraigned June 30. He has been charged with two counts each of first-degree sexual abuse and using a child in display of sexually explicit conduct.

The abuse reportedly took place after a swim lesson, police said.

It's really scary how they sneak in unexpectedly, said parent Diana Crawford. That's what kind of shocks me how this is happening with the club I love so much, that this can go on behind doors. That I would've never expected.

Prior to moving to the Sunset Athletic Club, Kelly worked at the Beaverton Swim Center on Northwest Science Park Road for about eight months.

After interviewing a number of people, investigators worry there could be additional victims. Anyone with information was asked to call the Washington County Sheriff's Office at 503-846-2500.

The general manager at the Sunset Athletic Club said safety of the club's members is a top priority. She said the club was fully cooperating with the investigation.

A man who provided massage therapy at Sunset Athletic Club was arrested in March for sexually abusing a 15-year-old girl.

More: Massage therapist arrested for teen sex abuse

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