Speaking to the Evening Standard, friends of the two men said they went to church every week, and were in the wrong place at the wrong time.
They were funny, kind, bubbly, outgoing and very charismatic. They had hearts of gold and always had big smiles.
If you needed something because you didn't have any money or whatever they would always help you out. It's such a shock. We have no idea who would want to do this.
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The plaque at number 16 Cowley Street in Westminster marks the brown brick Georgian townhouse where Sir John lived for 31 years.
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Metropolitan Police officer, Tom Harrison, has been crawling the course since the race began on Sunday morning.