ADELPHI, Md. (AP) — Police in Prince George’s County say a standoff with an armed man inside an apartment building has ended peacefully.

The barricade situation began Monday night at a building in Adelphi. Police negotiated with the man for about 8 hours before taking him from the building in an ambulance shortly before 6 a.m. Tuesday. Police say he was alone in the apartment.

Police say they had been assisting U.S. marshals in serving a warrant when the standoff began.

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