According to the above news report from ITN, visibility was down to 20 yards (approximately 60 feet). At the front of the pile-up are a number of cars, a semi-trailer and a fully-loaded car transporter.
Witnesses said many of the cars drove into the fog at speed and without their fog lights switched on. The crashes continued for a 10 minute period after the initial impact, they added.
The bridge remained closed for the rest of the day while the debris was cleared up.