Police say the accident happened between junctions eight and nine at about 1040 GMT when a lorry travelling north collided with a car and crashed through the central reservation.

Three other cars were involved in the crash, and the driver of a Vauxhall Corsa was declared dead at the scene.

The driver of the lorry was taken to the Luton and Dunstable Hospital, and three others were slightly injured.

Traffic disruption

The lorry, which was carrying a load of plasterboard, ended up on its side on the southbound carriageway.

The motorway has been closed between junctions 11 and eight southbound, and the northbound carriageway has been closed at junction six with the M25.

The M10 has been closed at the Park Street roundabout to ease the pressure of traffic.

The disruption is likely to continue throughout the evening.