(London Telegraph) Mr Bauman was waiting to see his girlfriend finish the race when a man in a white cap and sweatshirt dropped a backpack at his feet. The 27-year-old lost both his legs in the explosion.

Despite being heavily drugged, Mr Bauman got word to the authorities that he had seen one of the bombers.

He told FBI investigators that he looked in the eyes of Tamerlan Tsarnaev as he planted the bomb. He went on to identify him in a photograph.

Mr Bauman’s brother, Chris, said: “He woke up under so much drugs, asked for a paper and pen and wrote, ‘bag, saw the guy, looked right at me’.”

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