Mustafa Kanjo, son of former minister of state for foreign affairs Siddique Kanjo, was nabbed by Lahore police following the orders of Punjab Chief Minister Shahbaz Sharif.
Siddique was said to be associated with Prime Minister Nawaz Sharif's PML-N party.
SSP Investigations Ayaz Saleem confirmed that Mustafa Kanjo was arrested for allegedly opening fire near Cavalry Ground after an argument over a car accident.
The gunshot killed 16-year-old passerby Zain who was going somewhere on a motor-bike. His friend also sustained injuries in the firing that took place in Lahore last night.
There are reports that the victim's family was being reportedly threatened to withdraw the case.
Influential people in Pakistan are said to flout the law frequently who often go scot-free. There is a growing resentment in the country over police reluctance to nab such people.