Tiruvannamalai: Mangalam police registered a case and are investigating the reasons why a son clubbed his father to death on Friday night. Murugesh (52) a farmer of Padagam village near Mangalam in Tiruvannamalai district had a son Mithukumar whose wife Venda worked as a nurse at the Primary Health Centre at Kettavarampalayam. As Venda stayed in the PHC itself, Murugesh’s wife Devi also stayed there to help her. This lead to frequent quarrels between father and son Muthukumar seriously hurt father Murugesh with an iron rod. The latter succumbed on way to hospital and police arrested Muthukumar.