A man possibly armed with a knife barricaded himself inside a home in the Langley Park area for more than 10 hours before Prince George's County police officers were able to talk him out peacefully, authorities said Wednesday.

The Prince George’s County police department posted on Twitter at about 2:30 p.m.that the barricade had ended peacefully, and the man was transported to a local hospital for evaluation.

The incident began just before 1:20 a.m.Wednesday, when the man called 911 and seemed mentally unstable to dispatchers who answered the phone, said Lt. William Alexander, a Prince George’s County police spokesman. He said officers went to the man's house in the 8500 block of 14th Place to investigate what was wrong and saw him inside, possibly armed with a knife or other edged weapon.

Police declared a barricade situation and worked to coax the man outside, Alexander said. It remains unclear what precisely upset him. 

This post has been updated.