BLACK HAWK, Colo. --
Two casinos in Black Hawk were evacuated for about 90 minutes Wednesday after a pair of cases containing large air tanks were found in a parking garage, police said.
About 9:10 a.m., a security guard found the black cases, as big as medium-sized suitcases, near a pillar on the second-floor of the Riviera Casino garage, Black Hawk Police Chief Stephen Cole told 7NEWS.
The security guard called police, who summoned the Jefferson County bomb squad.
"Given the size of these suitcases, there was enough potential risk if there had been a device in there that it warranted evacuating the buildings," Cole said.
The Rivera Casino and neighboring Isle of Capri Casino and Hotel were evacuated about 11 a.m. and traffic on nearby Highway 119 was diverted, he said.
Bomb squad members X-rayed the cases and found each one contained a silver tank, similar to the air tanks firefighters wear on their backs when entering a smoky building, Cole said.
While it's not uncommon for older casino patrons to bring supplemental oxygen bottles, these tanks were twice as big as medical oxygen canisters, Cole said. The brand new-looking tanks also had a framework for straps, like the self-contained breathing apparatus a firefighter wears.
It's possible that a visitor just forgot the tanks while loading their car, the chief said. But it was unusual, because the Riviera Casino doesn’t have a hotel where people would be loading and unloading luggage, he added.
During the evacuation, buses from the Gilpin County School District and an ambulance where staged in the Lady Luck Casino parking lot to give evacuees a place to wait.
But it was a warm day and other casinos were open, so patrons had other ways to spend their time until the 90-minute evacuation ended at 12:30 p.m., Cole said.
The bomb squad removed the tanks, but investigators haven't determined if they contained oxygen or another gas, Cole said.
Black Hawk City Manager Jack Lewis praised city police and firefighters for their handling of the evacuation and thanked the Colorado Division of Gaming, Gilpin County Sheriff’s Department, the school district and casino staff for their assistance.
"Given the location of the packages and the results of the X-rays, complete caution was taken in handling and removal of the packages," Lewis said.
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