DETROIT (AP) -- Traffic again is rolling across the Ambassador Bridge, a U.S.-Canada span that was closed for hours while authorities checked out a bomb threat.
The threat came Monday night to the U.S. side of the bridge in Detroit. There was a similar threat four days earlier to a nearby tunnel crossing.
According to the Michigan Department of Transportation, traffic was at normal levels as rush hour approached Tuesday morning.
Detroit police say someone called 911 around 7:20 p.m. Monday, saying a bomb would go off in 10 minutes.
Sgt. Eren Stephens says the call prompted authorities in Detroit and Windsor, Ontario, to halt all truck and car traffic across the bridge. The bridge was reopened around 1 a.m. Tuesday after security sweeps failed to turn up any incendiary devices.
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