MUMBAI, May 28 -- A 35-year-old man was arrested on Wednesday for allegedly killing a 29-year-old neighbour who intervened in a fight between the accused and his elder brother on Monday. According to the police, the incident took place around 11.40pm at Ketkipada in Dahisar East. The deceased, identified as Sagar Gautam Sugire, 29, stepped in after his elder brother, Mahesh Gautam Sugire, 35. allegedly confronted their neighbour, Ram Dhudate, 36, accusing him of having an illicit relationship with his wife. Police said the accused allegedly abused Sagar before beating him up. He then allegedly grabbed the victim and threw him down a flight of stairs. Even after Sagar fell unconscious, the accused allegedly continued the assault using a stone, police said. Sagar was declared dead in the hospital. Based on a complaint lodged by the victim's family, the police registered a case under sections 103(1) (murder), 115(2) (voluntarily causing hurt), 352 (intentional insult with intent to provoke breach of peace), and 351(3) (criminal intimidation) of the Bharatiya Nyaya Sanhita....