A police officer fired his gun at the man when he refused to drop the sword.

When 28-year-old Balvinder Singh got into an argument with his parents this morning, he grabbed a sword hanging on their living room wall and attacked them. He went at 20 more people on the road before he was shot dead near his home in Telangana's Karimnagar.Balvinder, an electronics engineer who worked in Bangalore, was reportedly depressed after he failed to crack the civil service exams.At around 6.30 am, he had a fight with his parents and attacked them. His father, a schoolbus driver, was injured on his head and his mother, a teacher, was stabbed in the abdomen, the police said.Scared and injured, the elderly couple ran out of their third floor home, chased by their son.After leaving his parents unconscious and lying in blood, Balvinder started attacking passers-by and kept lunging at different people for 45 minutes, leaving a trail of blood spots over an area between 500 metres to one km.He first ran after an auto-driver with schoolchildren, then a black-robed "Ayappa" devotee and a biker. Someone called the police and a constable came to the spot.The constable had his little finger chopped off when he tried to overpower Balvinder.Another policeman arrived but when his weapon fell, Balvinder picked it up. That is when the constable shot him. He died in a local hospital.Balvinder's father Avtar Singh told the police that he had been "acting strange" in the past month and was even taken to hospital for psychiatric treatment."He was under depression as he couldn't get into civil services," said Rama Rao, Deputy Superintendent of Police.Balvinder reportedly earned Rs 18 lakh annually and was described as a meritorious student throughout.