A former director of a reputed pharmaceutical company allegedly killed his wife and two children before hanging himself to death at their Sector 49 residence here on Monday, police said.Prakash Singh (55) killed Sonu Singh (49), daughter Aditi (21) and son Aditya (14) at their residence in Uppal Southend residential colony in Gurugram on Monday morning.A suicide note recovered from Singh's pocket stated that Singh was "unable to handle his family".Police said the note had been sent to experts to find out if it was written by Singh, who had been living in Gurgaon for the past eight years. Singh's wife ran a private school. Aditi was studying in a college and Aditya in Class 10, the police said.Police said the neighbours alerted them."When we broke open the house, we found Sonu, Aditi and Aditya had injuries caused by a sharp object and a hammer. Singh was found hanging from the ceiling," said a senior police officer.The two weapons have been recovered.Prima facie, it appears that Singh killed his family while they were asleep.Police sources said a family member revealed that Singh was disturbed for the past one year.