Sumit Roy, the Personal Assistant to Trinamool Congress General Secretary and Diamond Harbour MP Abhishek Banerjee, who was arrested by the sleuths of the Criminal Investigation Department (CID) of the West Bengal Police in connection with an alleged multi-crore land-grabbing case in Salboni of West Midnapore district was on Friday remanded to eight days of CID custody by a district court in the same district.