Passengers on board a coach that sparked a terror alert which led to the closure of the M6 Toll for more than four hours have spoken of their ordeal.
They told of their fright when armed police swooped on the Megabus travelling from Preston to London after a fellow passenger reported seeing smoke coming from another's bag.
Armed officers, troops, firefighters and bomb disposal experts responded and attended the scene at around 8.20am on Thursday after the driver stopped on the hard shoulder of the toll road, near Lichfield, following the complaint.
Police later confirmed the device was an electronic cigarette which gives off a visible vapour.
Arriving back at Victoria Coach Station - some of them 13 hours after starting their journey - they spoke of their terror as they thought they might die during the episode.
Student Vermilion Von Kangur said: "I was scared. I thought there might have been a bomb on the bus."
The 48 people on board the coach were made to leave it one by one with their hands clearly visible as armed officers looked on with their guns poised.
Miss Kangur continued: "My legs were like jelly, I couldn't walk.
"I felt very intimidated. I thought if I moved I would get shot.
"The driver was talking to police but they weren't saying anything to us.
"Some people thought there was a bomb on the bus, some people thought it was going to explode.
"Some people thought the bus had broken down, or that there was a prisoner on board."
The 20-year-old, who was travelling to the capital from Preston with her friend Linzi Parker, 18, for a Marilyn Manson concert, added: "People thought they were going to die. They were calling their families.
"People didn't know what was going on so we only had to use our imaginations and picture the worst."
After learning it was a false alarm, Miss Parker told Sky News: "I feel it was over the top, but I can understand why they did it."
A Staffordshire Police woman said: "The information received concerned a report of vapour escaping from a bag which on investigation turned out to be a health improvement aid for smokers.
"Given the credibility of the information we received, we responded swiftly and proportionately.
"We can now confirm that, whilst this was a genuine security alert, the significant concerns reported to us were unfounded."
She went on: "It's important to state that no criminal offence has been committed and no passenger or any other member of the public is being treated as a suspect.
"Our utmost priority was the safety and security of the public and whilst on this occasion the incident was resolved peacefully without event, we want to encourage the public to remain vigilant and report any suspicious activity.
"We would like to apologise for any inconvenience and hope that the public understand that we have our duty to safeguard public safety."
The M6 Toll which was closed in both directions was reopened after police said the incident was not terrorism-related, no one was being treated as a suspect, there was no danger to passengers and no one had been injured.
Sky's Midlands correspondent David Crabtree said there had been suggestions that there had been "some kind of fluid poured into a bag that then started smoking" on board the coach.
Officers were seen searching the empty vehicle at it stood at the side of the southbound carriageway before it was later driven away with a police escort.
Soldiers from the Royal Logistics Corps bomb disposal unit were sent to the scene while fire and ambulance services set up decontamination facilities.
Crabtree added: "When I arrived there was a great deal of activity around the coach itself.
"It was a very carefully ordered operation of getting those people off the coach and to walk alone from the coach to the toll gate building itself - from one group of police to another.
"They were spoken to as they reached the second set of officers and then they were taken away."
A spokeswoman for Megabus, which is operated by Stagecoach, said the company was assisting police with their enquiries and that all the passengers booked on the service were safe and well and had been transferred to a substitute vehicle.
"We are making arrangements to provide onward travel for passengers as soon as we receive clearance from the police," she added.
Sky's crime correspondent Martin Brunt said the counter-terror command at Scotland Yard had been kept updated about the incident.
"Although we now have regional counter-terror units now Scotland Yard still holds the national brief," he said.
The closure of the motorway caused long queues throughout the morning.
Traffic information company Inrix said motorists avoiding the M6 toll closure used the M6 proper and were caught up in delays of up to two and a half hours on the southbound carriageway after an accident around junction seven.
Drivers wanting to avoid the M6 queues were advised to take either the A449 and travel through Wolverhampton to rejoin the M6 south of junction seven, or use the A34 and head south from Stafford.