WASHINGTON — (AP) A delegate to Congress says a group of 6- and 7-year-olds was mistreated by staff at the U.S. National Arboretum in Washington during a field trip.

Del. Eleanor Holmes Norton, a Democrat who represents the District of Columbia in Congress, says a staffer called an armed officer to respond when the first-graders were playing in an area where they apparently weren’t allowed.

Norton sent a letter to the director of the arboretum on Tuesday, asking for an apology to the students and teachers of Two Rivers Public Charter School. She says there were no signs telling visitors that the area where the children were playing was restricted.

Norton says the responding officer behaved appropriately and “de-escalated the situation,” but she says it was “likely a traumatizing experience for these children.”

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