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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Parents fear council plans to expand Aldryngton Primary School in Wokingham will make an already dangerous traffic problem, even worse.
Simon's Blog - Winter Wonderland
Tuesday night's weather for the west of the region