Martin Stammers was a witness to the crash. He told Yahoo News: "It's horrific. I've never seen anything like it in my life. All you could hear was cars crashing. We got out of our car and it was eerily quiet with visibility down to just 20 yards. Then you would hear the screeching of brakes and then a thud. It was all you could hear for about 10 minutes — crash after crash after crash.
"The whole top of the bridge is full of mangled cars and lorries. There are cars with their roofs ripped off — one is five feet in the air. There were a lot of people trapped."
Kent police were called to the scene at 7:15 a.m. BST on reports of collisions at both ends of the Sheppey bridge crossing. Officers are now urging motorists to avoid the area, and warned that those who proceed should expect long delays.
—By CNBC's Katy Barnato