Surendra Singh, 55, a senior official with the Punjab National Bank (PNB) here, first shot his wife Anamika, 50, with his .32 bore licensed-revolver at around 9 a.m. killing her instantly at their sector 5, Vikas Nagar residence, police said.
He then shot his 27-year-old daughter Niharika in the temple and as his 23-year-old son Nishant came to her rescue he shot at him before turning the gun on himself.
Nishant, who returned home recently after completing his engineering studies from Pune, was shot in the head but managed to dial 100 and inform the police.
The police rushed the profusely bleeding four to the trauma centre where Anamika was declared dead on arrival.
Niharika battled for life for a while but succumbed to her injuries, doctors said. Singh's condition is said to be extremely critical and doctors say his chances of survival were grim.
Nishant may, however, survive, doctors said.
Police have since sealed the house and seized the revolver used in the crime. PNB officials say Surendra Singh was feeling depressed for sometime.