Drivers fled their cars in panic after a vehicle burst into flames in the Dartford Tunnel this afternoon.

Emergency crews were called just before 1pm to the incident which has blocked the M25 clockwise.

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Footage posted online showed people leaving their vehicles to move away from the blaze.

Emily Dyster from Essex and her partner Jordan Riley were among those who found themselves stuck in the tunnel when the fire started.

VIDEO: Footage of drivers abandoning their vehicles to escape the blaze

"The traffic started slowing down as we came into the tunnel," she said. "No one knew what was going on but there was smoke coming down the tunnel.

"I got out to see what was going on. Everyone was screaming saying 'get out, there's a fire.'

"There were kids crying and no one knew what was going on."

Emily and Jordan, along with many others, were able to reverse their cars out of the tunnel; but she said there had been little help or information from tunnel staff or emergency services. Others abandoned their cars, but had to return to them to help fire crews gain access to the scene.

She believed the blaze itself was extinguished by automatic sprinklers in the tunnel.

But she added: "It was scary because we didn't know if the car was going to explode when it was on fire."

Crews from Kent and Essex are believed to be attending the blaze, with support from Kent Police.

Police say they received a report that a car was on fire at the Dartford River Crossing at 12.53pm.

There are no reports of any injuries.

Both tunnels have since been reopened although delays continued into the afternoon.