DMK president and former chief minister M K Stalin on Saturday criticised the BJP-led govt at the Centre for detaining former chief ministers Pinarayi Vijayan, Arvind Kejriwal and Mamata Banerjee, senior political leaders from various parties and student organisation leaders protesting against the Special Intensive Revision (SIR) of electoral rolls. He contrasted their detention with Chief Election Commissioner Gyanesh Kumar continuing to enjoy Z+ security, despite what he called acts of “treason”.