The Race2Recovery team is trying to complete the Dakar Rally to raise funds for Help for Heros.
The charity is raising funds for the Tedworth House recovery and rehabilitation centre in Wiltshire.
The two US Marines involved with the race are also raising funds for the Heros Project which supports injured service men and women in America.
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Rain will spread eastwards across southern areas tonight. Clear and frosty in the north.
Political leaders will go head-to-head at ITV's studios in MediaCityUK in Salford, ITV has confirmed, as the set for the event is unveiled.
More than 100 people claiming to represent working people across Britain have signed a letter backing Labour in the general election.