The body of a 70-year-old woman was kept hidden by her sons in their house in Varanasi for over four months for allegedly withdrawing her pension using her thumb impression, the police said. The body of Amravati Devi was recovered from the store room of her residence in Kabirnagar colony of the Bhelupur area after the neighbours informed the cops about a foul smell emanating from the house, they said. Devi died on January 13 and her five sons, Ravi Prakash, Dev Prakash, Yogeshwar Prakash, Jyoti Prakash and Girish Prakash, were using various chemicals to preserve her body, they added. The police also found ink marks on one of Devi's thumbs. Devi used to receive a sum of Rs 40,000 as pension after her husband Daya Prasad, who worked as a superintendent in the customs department, died a few years ago. The body has been sent for a post-mortem examination. No arrests have been made so far.