MUMBAI, June 9 -- A 60-year-old electrician allegedly shot dead his 53-year-old wife before dying by suicide at their Worli residence early Sunday morning, police said. The incident occurred while the couple's son and daughter-in-law were asleep in another room. According to the Worli police, the incident took place between 5:30 and 6:30 am at the family's home in a housing society in the area. Preliminary investigation suggests that a domestic quarrel escalated, prompting the man to shoot his wife at point-blank range with a country-made pistol. He then left the flat and shot himself on the building's staircase. The couple's son, 30, and his wife were reportedly asleep in their bedroom and claimed they did not hear the gunshots. The crime came to light when a newspaper vendor spotted the man's body on the staircase and alerted the building's security guard, who then knocked on the family's door. Upon waking, the son discovered his mother lying in a pool of blood in the hall. A subsequent search led him to his father's body on the staircase. The Worli police were called to the scene, and both bodies were sent for post-mortem examination. The police have registered a case of murder against the deceased man. Investigators are also probing how he acquired the illegal firearm. "Initial inquiries suggest the couple frequently argued. We've also been told that during family disputes, the wife would often support their son, which may have caused resentment," said a police officer. The man, a self-employed electrician, is said to have taken on small contracts in the neighbourhood. Police said the family and relatives are in shock and are cooperating with the investigation. "We are examining all angles to establish the exact sequence of events and motive behind the act," the officer added....