Frank Sinatra once served as a Mafia courier and narrowly escaped arrest with a briefcase containing $3.5 million in cash, according to a new biography of the legendary singer.

　　The entertainer Jerry Lewis is quoted as saying that Sinatra "volunteered to be a messenger for them... And he almost got caught once... in New York."

　　Extracts of Sinatra: The Life, an unauthorised biography by Anthony Summers and Robbyn Swan, were published yesterday by Vanity Fair magazine. Lewis said that Sinatra was going through customs with a briefcase containing "three and a half million in fifties" and that customs officials opened the case. But due to crowds jostling for a glimpse of the star, officials aborted their search. Otherwise, Lewis said, "We would never have heard of him again."

　　According to Vanity Fair, the authors do not claim that Lewis witnessed the customs incident but related the account "as a fact of which he had knowledge".

　　Lewis, one of the singer's Rat Pack compatriots from the 1960s, claims that Sinatra's mob links "had to do with the morality that a handshake goes before God". The anecdote is one of many fleshing out Sinatra's reputed close ties to the Mafia.

　　The singer carried mob money several times, Lewis is quoted as saying. He knew the Mafia was expanding beyond its East Coast base and volunteered to be a "messenger".

　　"Frank, at a cocktail party, told Meyer [Lansky, a known mobster] in no uncertain terms, 'If there is going to be East Coast, West Coast, intercontinental and foreign - if all that's going to happen, I go all the time," Lewis says.

　　Sinatra, who died aged 82 in 1998, always denied any links to the mob, although FBI files released seven months after his death portrayed him as a close friend of Sam Giancana, the reputed Chicago mobster.

　　The federal documents also suggested that he had contact with Mafia boss Lucky Luciano during a 1947 trip to Cuba and alleged that his early singing career was backed by a New Jersey-based racketeer named Willie Moretti.

　　The book quotes Lewis as saying that the cash smuggling incident occurred shortly after Luciano was deported from the US to Italy in 1946.

　　According to Vanity Fair, the authors of the book describe Sinatra's "long-time, intimate relationship with Luciano", who in 1936 was declared New York's "public enemy Number One", progressing from "beatings to no fewer than 20 murders to pioneering drug trafficking".

　　Sinatra said he did not meet Luciano until a chance encounter in 1947, but the book suggests that he had contact with "top New York area mobsters as early as 1938 or 1939". It also describes how Sinatra's mob links helped his career.

　　It quotes Sonny King, a friend of the singer, as saying: "The Boys got on to Frank. In part because he was a saloon singer and they loved saloon songs, and they liked his cockiness... They liked to think of him as their kid, or son."