They’ve been called many things: an “e-cig,” a personal vaporizer and, more practically, a smoking cessation device.

But an IED?

British counter-terrorism officers concluded Thursday that a bomb scare on a bus traveling on the M6 motorway, the longest in Britain, was spurred by a man’s electronic cigarette, according to the Associated Press.

This aerial shot shows fire engines, ambulances and emergency vehicles at the scene on the M6 toll motorway, around 116 miles north of London, after the motorway was closed following a terror scare on July 5, 2012. (Associated Press)

“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 told The Independent.

According to reports, armed police evacuated passengers aboard a London-bound bus as emergency response vehicles and a bomb disposal unit arrived on the scene. The 48 passengers on board were sequestered on the highway, surrounded by law enforcement, as police investigated the scene, shutting down the highway for roughly four hours. Police said they did not plan to hold any passengers in custody.

The emergency response came just a few weeks before the 2012 Summer Olympics in London.

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