DETROIT, July 20 (UPI) -- Detroit police are investigating four hoax bomb threats made within a week on Comerica Park, the Detroit-Windsor Tunnel and the Ambassador Bridge.
Police officials said Thursday a hoax bomb threat for the Ambassador Bridge Wednesday was the fourth of its kind within the week, the Detroit Free Press reported. Hoax threats were made for Comerica Park Tuesday, the Ambassador Bridge again Monday and the Detroit-Windsor Tunnel July 12.
The July 12 and Monday threats forced police to shut down the tunnel and bridge for several hours each day and bring in bomb-sniffing dogs and bomb squads. The threat on Comerica Park was made an hour into a Detroit Tigers game, but fans and media were not made aware of the threat until the game ended. Traffic was not disrupted in the investigation of the most recent Ambassador Bridge threat.
Police did not say whether one person or copycats made the hoax threats.
"This is an on-going investigation and there's a lot I can't share with you -- we don't want to get in a cat-and-mouse game with the perpetrators because they read newspapers, too," Detroit police Inspector Donald E. Johnson said.