The Coast Guard is warning of multiple "phosphorous pyrotechnics" that could be floating in Lake Michigan water or washed up on beaches after one was discovered on a Chicago beach this Memorial Day.
The Coast Guard Sector Lake Michigan alerted about the "unaccounted" devices Tuesday afternoon.
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WATCH HEREThe flares were deployed during a "joint military exercise with the Coast Guard and Air Force" earlier this month off the Milwaukee shoreline. According to the Coast Guard, four devices were deployed during the exercise but did not activate.
One pyrotechnic was later located by a lifeguard on Montrose Beach in Chicago on Memorial Day.
"Three phosphorus pyrotechnics are still unaccounted for," the Coast Guard said.
The Coast Guard warned "all beachgoers to remain clear and contact 911 should they locate a silver shaped cylinder along the beach."
"These are phosphorous pyrotechnics that produce a red smoke and flame that can reach temperatures of 2900 degrees Fahrenheit," the Coast Guard said in its alert.
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