PHILADELPHIA—A 13-year-old suburban Philadelphia girl reported missing has been found in Washington, D.C., with a 20-year-old man she met online.

Acting on a tip, U.S. Marshals located Radnor teen Savanna Marie MacMullett as she exited a bus in the nation's capital Tuesday night. She was with Ashley Ryan Hareford, who was taken into custody on a corruption of minors charge.

MacMullett had been last seen at 4 p.m. Monday when she left her house and told her parents she was headed to an after-school activity.

Hareford, who's from Virginia, devoted several of his Facebook posts Monday to MacMullett.

Police in the area of the girl's house stopped Hareford Sunday night because he was acting suspicious but released him without taking him into custody.