Chandigarh, Jan 11 : Acting tough, Punjab Chief Minister Bhagwant Mann on Wednesday asked the striking Punjab Civil Service (PCS) and revenue officers to join duty by 2 p.m., otherwise strict action will be taken against them. In an official letter to Chief Secretary V.K. Janjua, CM Mann asked him to suspend all those officials and employees who do not join their duties by the given time framework. He said that the officials and employees were trying to blackmail the government by exerting pressure and protecting the corrupt. This action of employees is "blackmailing and arm twisting", he said. "We have zero tolerance to corruption", he said while adding that the strike could not be tolerated by any responsible government. Members of the PCS Officers' Association proceeded on a five-day casual leave on Monday to protest against the arrest of their colleague Narinder Singh Dhaliwal, secretary, Regional Transport Authority (RTA), Ludhiana, who was arrested by the Vigilance Bureau on January 6 in a corruption case. At least 235 PCS officers across Punjab are now on mass casual leave. The union will be announcing their next course of action on January 14. The offices of deputy commissioners, civil secretariats, divisional commissioners and revenue offices wore a deserted look. /IANS