Lucknow, Sep 1 : Three persons have been detained for interrogation in connection with the murder of a youth at the residence of Union Minister Kaushal Kishore in Lucknow on Friday. The youth, a friend of the minister's son, was shot dead on Friday morning with a pistol that belonged to the minister's son, Vikas Kishore. Meanwhile, the minister told reporters that while his son was in Delhi at the time of the incident, he had asked the police to carry out an impartial and thorough probe in the matter. 'The pistol that police have recovered belongs to my son, Vikas Kishore. Police are conducting a thorough investigation. The culprits will not be spared. Vikas Kishore was not at the residence when the incident took place. Police have detained his friends and the people present there when the incident took place. Vikas was extremely sad when he got to know about this, the deceased Vinay was a very good friend of my son," he said. Vikas Srivastava, brother of the deceased said, 'My brother Vinay Srivastava has been killed at the residence of Union minister Kaushal Kishore. My brother was a friend of his son Vikas Kishore. Three people were present there when the incident took place but I do not have any idea where Vikas Kishore was when the incident took place. His licensed revolver was recovered by police from the spot.' The body of the deceased has been taken for post-mortem. /IANS