Calcutta, Aug. 11 : Calcutta, Aug. 11: Almost five months after the payment crisis rocked the Calcutta Stock Exchange (CSE), heads have started rolling at the city bourse. The first casualty was executive director Tapas Datta whose service the CSE board terminated today. "The decision was taken at the board meeting today after considering Sebi's inspection report and Datta's explanations. The board and Sebi are of the view that there was lack of action on his part," Dipankar Basu, who is the chairman of the CSE management panel, said. He indicated that action may be taken against other exchange officials as well.