A cloth merchant and his two sons were shot dead allegedly by some unidentified assailants at their house in Ghaziabad early on Monday, police said.
The trader's wife, who also suffered gunshot injuries, is currently hospitalised, Ghaziabad Superintendent of Police Amit Pathak said.
"The incident took place around 3 am in Toli Mohalla in Loni police station area," the officer said, adding police teams, including forensic experts and dog squads, have been sent to the incident spot.
"No loot or robbery has been reported yet. We are looking into various angles in the case," Mr Pathak told PTI.
Those killed have been identified as merchant Raisuddin, his sons Azharuddin and Imran.