State additional director general of police (crime investigation department) Ram Singh Meena reviewed ongoing investigations of the cases of Dehradun and Haldwani CID sectors with the officers concerned and gave them necessary instructions to improve quality in investigations on Tuesday. He stressed on collecting evidences scientifically and solving pending investigation of the cases at the earliest. Others present were IG (CID) Anant Ram Chauhan, additional SP Dehradun sector Shweta Choubey and Pankaj Bhatt, additional SP of Haldwani sector.