By Leon Watson PUBLISHED: 06:42 EST, 2 December 2013 | UPDATED: 12:06 EST, 2 December 2013 A frail grandfather was beaten up in his own home by two self-styled vigilantes who wrongly suspected him of being involved with the theft of their Christmas presents. Christopher O'Brien, 36, and his 26-year-old nephew John Bonner, boasted after the brutal assault on Norman Sheldon who died six days later. Despite protesting that he knew nothing about the disappearance of the gifts from Bonner's house, O'Brien repeatedly punched the 47-year-old grandfather in the face, causing him to hit his head against a wall.
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Christopher O'Brien, 36, and John Bonner, 26, were hunting burglar
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They boasted after beating up Norman Sheldon, who died six days later
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Mr Sheldon, of Openshaw, Manchester, had denied involvement in theft
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O'Brien admitted manslaughter and Bonner pleaded guilty to affray
Their search took them to Mr @placeholder's home in Openshaw where Bonner confronted Mr Sheldon on the doorstep demanding that he tell him if the man responsible for the burglary was at the house.