DETROIT (WWJ/AP) – Comerica Park is the latest Detroit landmark to be the subject of a bomb threat.

Police said an anonymous caller issued the threat in a 911 call around 8 p.m. Tuesday as the Tigers were hosting the Los Angeles Angels in front of 34,000 fans. The Tigers lost 13-0.

No announcement was made, nor was there a call for an evacuation as police searched the ballpark for an explosive device.

Inspector Don Johnson of Homeland Security, along with other police and park security, searched Comerica, but no suspicious device was found and police gave all-clear by 11 p.m., Detroit police Sgt. Eren Stephens said.

The threat followed similar incidents in less than a week that shut down two international crossings for hours.

On Monday, the Ambassador Bridge was closed for roughly five hours after Detroit police received a 911 call pertaining to a bomb on the international bridge. The caller reportedly said a bomb would go off in 10 minutes along the busy freight crossing — but nothing was found.

Just four days earlier, a bomb threat to police in Windsor led to a four-hour closing of the Detroit-Windsor Tunnel. In this case, Canadian authorities were contacted by an anonymous caller from a pay phone in Windsor. Nearby freeways were also closed and the U.S. Coast Guard was stopping boats and freighters from traveling near the tunnel. Officials reopened the tunnel after sweeps proved the threat a hoax.

Speaking live on WWJ Newsradio 950 on Wednesday Johnson said there was also a bomb threat called in this week to Cobo Center, and another to the IRS building.

Johnson with said it would have been up to the ballpark to order an evacuation, but said that they had several layers of security in place.

“We felt very comfortable in what we had in place working together over the years, as a matter of fact, for this type of phone call,” Johnson said.

“The threat was not specific,” he added.

Johnson said investigators aren’t sure if any or of these threats are related.

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