David Myerscough stepped in for an ill colleague on Thursday morning to drive the blue Megabus from Preston to London when a passenger called police and reported smoke coming from a fellow passenger’s bag.
The 38-year-old father-of-two was called by his control room and told to pull the coach on to the hard shoulder at the M6 toll plaza near Lichfield, Staffordshire, and not to let anyone off.
“Once we pulled over, the police told me to make sure nobody left the bus,” he said. “After a while, we realised that the road beside us had actually been closed and cars had stopped going past us.”
Dozens of armed officers, troops, firefighters and bomb disposal experts all swooped on the scene, setting up decontamination units and makeshift pens on the carriageway.
Motorists faced long delays as the motorway was shut in both directions for more than four hours, but it emerged the alert was prompted by a passenger using a fake electronic cigarette which emitted a vapour.
Mr Myerscough said that once the passengers saw the armed police, “they calmed down and realised that we were going to have to go with it”.