Two "inert" grenades sitting inside a white powder were the source of concerns that led to the partial closing of the Ambassador Bridge connecting Windsor, Ont., and Detroit for about seven hours Monday.
The grenades were found by Canada Border Services Agency (CBSA) members during a vehicle inspection around 9 a.m. ET and Windsor police were alerted.
"The immediate area of concern had been evacuated prior to police arrival and the driver of the vehicle was in the custody of CBSA," according to the release sent out Tuesday.
"Through investigation, no other persons were believed to be involved in the incident and it was determined no direct threats were made specific to persons or places in connection with the grenades."
The explosives-disposal unit was deployed to the scene and a robot was used. The unit got some of the powder and tested it, finding it "did not contain energetic properties and was also not hazardous."
There was no intent to cause harm or use the grenades for any nefarious purpose. — Windsor police
A member of the unit was able to get the grenades from the vehicle, inspect them and determine they were chemically inactive.
The vehicle was thoroughly searched to ensure no other threats were present.
No charges are being laid by Windsor police, so the man won't be named.
"Investigation revealed that there was no intent to cause harm or use the grenades for any nefarious purpose," the release said.
"The grenades were inert, as such, not subject to any criminal charges being laid."
The driver of the vehicle, a man from the United States, was turned over "to the custody of U.S Customs and Border Protection without incident."
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