Ed Sheeran has discovered he is related to a murderous mobster who used to paint houses by splattering the walls with his victims' blood.

Ed Sheeran realised the connection when a movie was being made on the infamous hitman Frank Sheeran, allegedly a "distant uncle" of the singer. Martin Scorsese's new film "The Irishman", based on true events, stars Robert De Niro as Frank Sheeran.

Stephen Graham, who plays fellow gangster Anthony Provenzano in the popular new film, insisted that the connection between the two Sheerans is genuine.

"They're related, you know. Honest to God — I swear on my nana's life. That's what Ed said, he says it's his distant uncle," the 46-year-old told The Sun.

Earlier also, when the film was first announced, Sheeran had pointed out that he shares his name with the gangster, though probably unaware of the relation at the moment. The 28-year-old had written on social media: "Robert De Niro is playing a top Irish gangster in a new Martin ­Scorsese film. The gangster he is playing is called Frank Sheeran. True story."

The movie is an adaptation of the biography "I Heard You Paint Houses" by former prosecutor Charles Brandt, who interviewed Frank Sheeran before he died of cancer in 2003. The movie depicts Sheeran as an old man reflecting on his role in the disappearance of union labor leader James Hoffa (Al Pacino) and his connections to the Bufalino crime family.

The disappearance of Hoffa had been one of America's greatest unsolved crime mysteries until Sheeran came forward and claimed he murdered Hoffa by shooting him in the back of the head twice in a house in Detroit. The Irish gangster had committed several murders on the orders of Hoffa before killing him.

Ed Sheeran
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In the biography, Sheeran confessed he developed his murderous instincts when he served in the US Army in North Africa and Italy during World War II. The hitman told Brandt he spent 411 days in combat, far more than most other US soldiers and took part in executions of several German POWs including mule drivers.

On the professional front, the "Shape of You" singer announced in August he is taking a break from performing. "This is my last gig for probably 18 months," the singer said at his final show.

Ed Sheeran