The overturned tanker on the M2AN overturned tanker brought the M25 near St Albans to a standstill for most of Saturday after chemicals, diesel and oil spilled out onto the carriageway.

The articulated tanker, with a German licence plate, skidded across the motorway near Sainsbury's in London Colney between junctions 22 and 21a, and went up the embankment, before hitting the central reservation and tipping over at 11.30am.

The driver of the tanker, which was carrying non-toxic plastic chemicals, managed to free himself from the cab before the fire service arrived and escaped without any serious injuries.

No other vehicles were involved in the incident and the westbound carriageway was closed between junctions 22 and 21a until 6pm that day, while recovery crews attended to the scene.

Kartec Recovery of Greenhill Crescent in Watford, which was called out to recover the vehicle, described it as a complex operation involving the use of three heavy recovery vehicles with five heavy winches.

A spokesman for Kartec said: 'It was a mass operation.

'The tank had ruptured which meant there was diesel, oil and glass all over the carriageway, and the tractor unit of the vehicle had become detached from the trailer.'

Police are carrying out further investigations into the cause of the accident.