Lucknow, Jan 1 : The autopsy report of a four-year-old boy, Ayan Valmiki, who went missing for 16 days before his body was recovered from a drain in Uttar Pradesh's Barabanki, has revealed that ante-mortem head injury as the cause of death. The family had announced a reward of Rs 1 lakh for information about the child who had gone missing after going to buy sweets on December 14. A senior doctor said the viscera had been preserved and sent for chemical examination. Though it was over 16 days since the boy went missing, his death was found to have taken place only five days ago, he said. 'We have spoken to the neighbours and taken their statements and so far, no foul play has surfaced,' said Superintendent of Police Barabanki, Dinesh Singh. Local police have been directed to investigate all the angles. The boy's father told media persons that he had come with him to visit a doctor's clinic in Barabanki and also visited his brother-in-law's place in the nearby Ujjwal Nagar on December 14. He said his son was playing outside the house and stepped out to purchase sweets from a local shop but did not return even after 30 minutes. He reported the matter to the local police and a missing FIR was registered. 'We rushed in today after coming to know about the recovery of a body from the drain and identified it as that of my son,' he said. /IANS