Gwyn Williams was over taken by the ambulance shortly before the crash in the New Forest and told ITV Meridian what he saw.
He had been driving along the A336 between Brockenhurst and Lyndhurst in the New Forrest.
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Passengers who were on a BA plane bound for Gatwick have filed a lawsuit after it caught fire.
Saturday morning's weather for the west of the region
Saturday morning's weather for the east of the region