A bomb threat led authorities to close one of the busiest bridges between the US and Canada on Monday, just four days after a similar threat closed a nearby commuter tunnel that also connects Detroit to Windsor, Ontario.
Detroit police said a call came in at about 7:20pm to authorities on the US side of the Ambassador Bridge. The caller warned that a bomb would go off in 10 minutes along the busy freight crossing, police Inspector Don Johnson said at a news conference on Monday night.
The call prompted authorities in both cities to halt all truck and car traffic across the bridge, police spokeswoman Sergeant Eren Stephens said.
She said the bridge remained closed at 12:30am yesterday as the search of the bridge continued.
There were no immediate reports of authorities finding a bomb, though helicopters continued to fly overhead late on Monday night. Police had set up several roadblocks near the bridge, where canine units were called in to search the bridge. The coast guard was patroling the Detroit River beneath the bridge and blocked river traffic.
The closing led to major traffic backups on expressways and other major roads leading into downtown Detroit, Stephens said.
Car and light truck traffic was being diverted to the Detroit Windsor Tunnel about 3km away, though large trucks cannot use the underwater commuter tunnel.
A similar threat was phoned in on Thursday last week to Windsor authorities that led to a four-hour closing of the Detroit Windsor Tunnel, a busy border crossing beneath the river that also connects the two border cities. No explosives were found.
At the time, police said a man had called from a street pay phone and warned of a bomb on the Canadian side of the tunnel. Authorities have since said surveillance video from a coffee shop near the phone booth where the call was made might offer clues about the caller.
Stephens said Detroit police were leading the investigation into the bridge threat and working with state and federal law enforcement agencies.
Johnson said the call came in from somewhere in Detroit, though other details were not immediately released.
Dan Stamper, president of the company that owns the bridge, told WJBK-TV that crews thoroughly inspected the bridge and had found no signs of explosives by Monday night.