Paramedics performed emergency surgery on a 66-year-old man at the scene, but he suffered a cardiac arrest and was pronounced dead.
His brother, who is in his 70s, also suffered chest injuries.
He was airlifted to Frenchay Hospital near Bristol, where he remains (Tuesday).
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Feeling cooler, becoming unsettled
Becoming unsettled, feeling cooler
A couple on a mission to travel by train to every station in Britain have visited the least-used station in the West Country this weekend.