An entire fleet of armoured vehicles in Afghanistan is being fitted with stronger armour following the death of a West-based Royal Marine in a mine blast, an inquest heard yesterday.

Corporal Damian Mulvihill , 32, was killed by a bomb while leading a mission to clear Taliban fighters in the Sangin area of Helmand Province.

He was the front seat passenger in a Viking armoured vehicle when it drove over a mine which triggered and ripped through the floor.

The explosion caused the undercarriage to shoot upwards, trapping the 6ft 6ins Royal Marine in his seat and causing fatal injuries to his chest, legs and head.

An inquest heard the floor of the Viking was ''insufficient'' to protect its crew and passengers and nothing could be done once the device had exploded.

The death of Cpl Mulvihill, who was serving with the Taunton-based 40 Commando, on February 20 last year sparked an immediate review of the vehicles' use which will now see a reinforced platform fitted under each one.

Lieutenant Colonel Andrew Teare, who works in defence, equipment and support for the MoD, announced the plans at an inquest into Damian's death.

He said: ''In my opinion the vehicle was attacked by a mine or explosive that simply overcame the structure of the vehicle.

''The floor lifted into the cab and that caused the injuries to Corporal Mulvihill. The front right track rolled over some sort of pressure pad, activating the device.

''Enemy forces are bound to try and attack and defeat the friendly forces. It would appear they have simply added more explosives.

''Following his death, an urgent request came through from theatre to do something about this and provide more protection.

''A new armour has been designed and constructed which will provide further protection to the underside of the Viking vehicle.

''Six have been made in Britain and are being shipped out to Afghanistan. By April all of the Vikings in theatre are expected to be kitted out with the new platform.''

Vikings are armoured all terrain vehicles able to operate anywhere in the world in temperatures ranging from -46c to +49c.

They have been used for some time but the inquest heard Taliban fighters had evolved and are using higher amounts of explosives in their bombs.

There are 50 Vikings being used by British troops in Afghanistan, 45 on regular patrol and five spares.

The inquest, in Plymouth, Devon, heard Cpl Mulvihill, from Plymouth, was part of a five Viking convoy conducting a clearance patrol when he died.