ROCHESTER, Minn. (AP) -- Rochester police don't know why a masked man threatened a group of children with a gun in a school yard.

It happened early Wednesday while the children were playing outside Gage Elementary School.

The man ran away as police arrived. Officers later found a paintball gun and a mask near the school.

A possible suspect was found a few blocks away. He was interviewed and released for lack of evidence.

The children were playing behind the school when they spotted a masked man watching them. They ran when he approached carrying a gun.

The Post-Bulletin reports three of the children were let inside a nearby home to call police. But two others were caught by the man, who pointed a gun at them and told them to sit down.

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