Alauddin, 26, was arrested immediately after he shot dead Feroze yesterday.
Alauddin worked as a labourer in a showpiece gramophone manufacturing company where Feroze was the contractor, said A K Singla, DCP (north east).
Feroze was rushed to GTB Hospital where he was declared brought dead by the doctors.
“In her statement, Feroze’s wife said that her husband had told her that Alauddin was after his job and might kill him,” said the officer.
While Feroze’s family has alleged that Alauddin had planned the act, the accused claimed that he was teaching Feroze how to use a gun when he accidentally shot him, police said.
A case under section 302 of the Indian Penal Code has been registered at the Khajuri Khas police station and further investigation is underway to determine the motive behind the murder, the officer said.