MP Gareth Johnson has said “lessons must be learnt” about the Dartford Crossing after motorists were stuck for over seven hours.

A robot had to be deployed by police after a full-scale emergency was sparked when a man claimed he had a bomb on board a coach heading for Dover.

Up to nine miles of traffic built up after a 27-year-old from Bournemouth jumped off a coach near the tolls on Friday evening.

Speaking this week, the Dartford MP said: “We need to learn lessons from Friday’s incident.

“I have met with the Secretary of State for Transport about the incident and I am meeting soon with the borough’s chief superintendent so we can look at ways of improving things for drivers who were kept waiting for an incredibly long period of time.”

The 27-year-old man, a foreign national, was detained by security guards at a nearby depot and police arrested him at 4.15pm.

It is alleged he made threats about a device on the coach, which had gone through the toll booths.

Police cleared the vehicle of passengers and the surrounding area. Inside was a heavily sealed bag containing a cylindrical device with wires.

Bomb experts used a robot to examine the package.

The man is now being held at a secure unit after being detained under the Mental Health Act.

The man arrested was earlier held on suspicion of making a bomb hoax.

As miles of queues built up at the crossing, with both sides shut, it was said there were further threats of a device on a coach on the A20 in Dover.

Police stopped a coach at 6pm on the A20 and it was evacuated. Nothing was found and the A20 was reopened at 10.45pm.

Passengers on the coach in Dartford were taken from the scene, interviewed and released in the early hours of Saturday.

Among those trapped on the roads was former EastEnders actress and chYps supporter Cheryl Fergison who was on her way to appear on Channel 5 programme Big Brother’s Bit on the Side.

Meanwhile X Factor star Joe McElderry was 15 minutes late on stage at The Woodville to ensure those caught up in the traffic made it to the Gravesend theatre for his performance.

A Mr Whippy van gave out ice creams to those sat waiting, with Anna Stanford tweeting: “Glad I found myself next to Mr Whippy; 99s all round on the M25.”

On Google, “Dartford Crossing” became the third most searched phrase of the day with more than 100,000 hits.

Drivers heading to Kent across the bridge were being turned around and sent back to Essex.

Motorists attempting to use the tunnels to Essex were diverted along to the Blackwall Tunnel.

When the roads finally reopened, just before midnight, a number of lorries had broken down causing extra congestion.

Assistant chief constable Rob Price said: “We were dealing with a very challenging situation, with two scenes in extremely busy areas.

“Our main priority was to ensure the safety of the public, our officers and our partners at the scene.

“We received threats of a very serious nature that required regional and national co-ordination and declared this a critical incident.

“Obviously a lot of people were caught up in long delays but this could not be avoided as we had to ensure public safety and as soon as clearance was obtained the road was immediately opened.”