Gorakhpur, Sep 20 : A 55-year-old woman was killed when she tried to rescue her son from a local muscleman who were attacking him for filming a fist fight on his cell phone. The incident occurred in the Gulaharia Bazaar area of Uttar Pradesh's Gorakhpur on Monday evening but the FIR was lodged on Tuesday after which two persons were detained. The victim, Yashoda Devi, was trying to protect her 15-year-old son, Vikki, who had been attacked by Balwant Singh and hisdaughter, Khushboo, the police said. According to police, Singh and one Prakash Sharma had got into a fist fight. Vikki, who was standing nearby, started filming the exchange of blows on his cell phone. Singh became enraged and attacked Vikki instead. When Yashoda Devi intervened, Singh attacked her with a brick. She suffered a blow on the chest and was knocked unconscious. She died on the way to hospital. Gulaharia Bazar SHO Jai Narain Shukla said police have detained Singh and his daughter. 'We are investigating the incident and have registered a case of culpable homicide not amounting to murder,' he said. 'Based on preliminary information, it has surfaced that there is an old property dispute between Balwant Singh and Prakash Sharma in Bargadhahi village,' said Shukla. /IANS