A tigress killed a man in the Mohraina forest range of Lakhimpur Kheri district in Uttar Pradesh, official sources said here today. Ramesh (30) had gone to the forest to collect firewood on Friday. When he did not return, members of his family tried to trace him. They spotted a mutilated body of Ramesh and the tigress sitting next to him in the forest yesterday, they said. Divisional forest officer R.C. Jha has issued a warning to the people not to venture into dense forest.