DETROIT (WXYZ) - About two blocks from the tunnel entrance and border crossing on the Canadian side of the Detroit River is a Bell telephone booth. Officials say someone used a phone there to call in a bomb threat tThursday afternoon .
Two phone booths sit on the edge of Senator David A. Croll Park, on Goyeau Street, about 100 feet south of University Avenue in Windsor.
Just after 5 p.m. Thursday, one of the two phone booths was blocked by a small amount of yellow police tape.
Law enforcement officials say they've dusted for fingerprints.
They say a call was made around 12:30 p.m. to a duty free shop near the entrance to the Detroit-Windsor Tunnel.
"Within two minutes of receiving the call we evacuated the tunnel in both directions," said Carolyn Brown, Executive Vice President of the Detroit-Windsor Tunnel.
"Customs on both sides cleared the folks who were in the tunnel relatively quickly," she said.
The phone call caused border security, local law enforcement and Homeland Security officials to mobilize on both sides of the international border crossing .
The Michigan Department of Transportation says the tunnel is the second busiest border crossing between the United States and Canada . For four hours, that traffic halted.
In the Detroit River, above the tunnel, Coast Guard and local officials turned vessels of all sizes around. Small boats and large freighters were all forced to avoid the waterways near the underwater crossing.
All afternoon, the border crossing remained closed as crews swept the tunnel before eventually issuing an all-clear and reopening the tunnel around 5 p.m.