Rapper 50 Cent is under fire for stealing his stage name from murdered New York City gangster KELVIN MARTIN who terrorised the streets of Brooklyn in the 1980s.

The late gangster's family are furious with the superstar rapper, real name CURTIS JACKSON, because they believe he is capitalising on their family's notoriety.

And now they want a share in the GET RICH OR DIE TRYIN' star's newfound fortune.

Martin's aunt fumes to the New York Daily News, "I think he's reaping all of the rewards of using the name and not sharing what he's getting."

But the rapper explains, "I took the name 50 Cent because it says everything I want it to say. I'm the same kind of person 50 Cent was. I provide for myself by any means."

And he promises to pay for a memorial to the late gangster in honour of his violent ideologies. He insists, "He'll never be forgotten, I'm dead serious. I'll see to it."