Wednesday night around 11 p.m., Mandan Police Department responded to an agency assist call from North Dakota Highway Patrol on Bismarck Expressway.
MPD says the call was regarding a combative male holding a knife to his own throat.
MPD says he began moving towards traffic and onto the freeway.
They were able to taze him and take him into custody.
MPD says the bridge was shut down briefly but has since been reopened.
Officials say they can't confirm why the man was on the bridge.