"What happened in the coppice that night might never be known, " he said.

BBC: Fuller quarry deaths: Children 'unlawfully' killed

The four bodies were found at Poles Coppice at Pontesbury Hill, near Shrewsbury, on 16 July.

BBC: Memorial for Fuller family in Coleford after quarry deaths

Lord Bach said the government was offering financial support to farmers who chose to grow short-rotation coppice, like willow, to help them make ends meet while the crops grew.

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