detroit tunnelThe international commuter tunnel connecting Detroit and Windsor, Canada has been closed as of Thursday afternoon  as authorities investigate a bomb threat which was phoned in on the Canadian side of the border according to tunnel executive Neal Belitsky

The tunnel is a busy one, with 4.5 million vehicles using it in 20122. It stretches about a mile underneath the Detroit River which connects downtown Detroit and downtown Windsor.

In service since 1930, the Windsor tunnel is the sister border crossing of The Ambassador Bridge which is located just west of downtown Detroit. That passage remains unaffected.

The source of this report was alertsUSA.