Delhi metro commuters may face tough time from Saturday as Metro's 9,000-odd non-executive employees have threatened to go on a strike from june 30 after little headway during talks between the management and the workers. The non-executive workforce including train operators, station controllers, technicians, operations staff, maintenance staff, havebeen protesting since june 19 at various depots and control rooms of the Delhi metro for revision of salaries and other issues. The workforce play a critical role in in running the the metroand the strike totally cripple the services. last year too, metro services had come to the brink of a shutdown when the non-executive staff had threatened to go on strike on similar demands. the crisis was, however, averted at the last moment after the DMRC managements and staff council came to an agreement following a series of meetings. The employees are demanding pay hike, payments of arrears, right to form a union and fixed guidelines for sacking an employee only in extreme conditions.