A three-year-old girl found dead in a field in Uttar Pradesh's Lakhimpur Kheri on Thursday morning was raped and strangled, the police said today. This is the third rape-murder in the district in the 20 days. The girl had been missing since Wednesday. Her body was found near just half a kilometer from her home with signs of head injury. Yesterday, the police had called it a murder. Sexual assault was confirmed by the autopsy, said the police.