A 30-year-old man shot his hedge fund founder father dead inside his New York apartment after the pair argued over the son's allowance.

Thomas Gilbert Jr was arrested on charges of murder and criminal possession of a weapon over the death of Thomas Gilbert Sr, 70, in Manhattan. He was being held pending arraignment and the law office representing him had no comment.

Police said Gilbert Jr went to his parents' home on Sunday afternoon and asked his mother to go out to get him some food. About 15 minutes later, she got a "bad feeling" and came back, said Robert Boyce, the chief of detectives for the New York Police Department.

"She found Senior on the floor with a bullet hole in the head," said Mr Boyce. "She also found a gun resting on his chest with his left hand covering it."

But Mr Boyce said it was a "staged suicide" - his son was trying to cover up the killing.