three books on the brothers and says Ronnie told him the twins dark secret during one of their chats.

He says while he knew about the the incest he waited until the brothers were both dead before revealing it for fear of retribution.

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Ronnie died in Broadmoor secure hospital of a heart attack in 1995 and Reggie died of cancer in 2000 having been released from prison on compassionate grounds.

In his book Notorious: The Immortal Legend of the Kray Twins , John said the pair were spoilt by their mother Violet, Grandma Lee and their two aunties, May and Rose, while their father was soon dominated by the increasingly violent brothers.

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Johnwith each other.”

The brothers ran a notorious criminal network in the 1960s building up an empire of nightclubs though hijacking, armed robbery and arson.

As they moved from the East End to the West End their became big names rubbing shoulders with Frank Sinatra and Judy Garland and being photographed by David Bailey.

Eventually the police got them and the Krays went to prison for murdering fellow gangsters George Cornell and Jack McVitie.