The security alert, which led to the closure of the M6 motorway, started after a passenger called police around 8:20 a.m. and reported seeing vapor seeping out of another passenger's bag.
The bus was stopped at Weeford, where police escorted passengers off the bus and closed the road for more than 4 hours, The Independent reported.
"The information received concerned a report of vapor escaping from a bag which on investigation turned out to be a health improvement aid for smokers," a police spokeswoman said. "It is important to state that no criminal offense has been committed and no passenger or any other member of the public is being treated as a suspect."
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