A man, along with his three children, committed suicide by consuming poison-packed bananas in Agra on Friday, police said.The incident of collective suicide took place under Taj Ganj Police Station area of the city.According to neighbours of the deceased, Man Singh, 45, was suffering from depression since his wife's death some time ago following prolonged illness. He had tried to end his life twice earlier but survived, they told the police.The neighbours on Friday morning saw all the four lying on the ground with white froth oozing from mouth. They were immediately rushed to a nearby hospital where doctors declared Man Singh and his 11-year-old daughter Archana dead.The other two kids -- Roopesh and Abhay -- are in critical condition, police said quoting the doctors.