Over 75 per cent of India's daily coal output has been hit as the five-day strike by workers of state-run miners entered the second day today, raising fears of disruption in power supplies. While talks between the striking workers union and the government resumed today with Coal and Power Minister Piyush Goyal deciding to intervene, there were reports of clashes between workers and police in Jharkhand. Besides Goyal, those involved in the discussions included Coal India Chairman Sutirtha Bhattacharya and senior Coal Ministry officials. As many as 290 out of 438 coal mines of state-run Coal India Ltd (CIL) had to be shut because of the strike, which is being termed as the largest industrial action in four decades, while many other mines across the country have also been hit. There are concerns that the strike may severely hit fuel supply to over 100 thermal power plants across the country, as the emergency coal arrangements may not last long. The state governments in Uttar Pradesh and Madhya Pradesh, among others, expressed apprehension about possible electricity crisis if the strike continues for a longer period, and that they are monitoring the situation. Unions alleged that CIL management was trying to bring in temporary workers to operate the 290 shut mines. As talks with Coal Secretary Anil Swarup failed to yield any positive outcome late last night, union leaders said they wanted political leadership to come to the negotiating table. The strike call has been given by all five major trade unions, including BJP-backed Bharatiya Mazdoor Sangh (BMS), against "disinvestment in Coal India and denationalisation of coal mining". "The strike has turned aggressive today. More than 75 per cent of the production has been affected. Most of our mines are badly hit," a top Coal India official told PTI. The unions said that about five lakh coal workers are on strike and that the protest will intensify going forward as the government has deployed police forces, resulting in clashes. Workers unions also claimed all of the 1.5 million tonnes a day coal output of the world's largest miner had been hit by the strike, but Coal India said over 75 per cent output has been impacted. AITUC President Ramendra Kumar said: "Agitation has turned aggressive today and the output hit is to the tune of 1.5 million tonne (MT) per day." Indian National Mineworkers' Federation (INTUC) President Rajendra Singh warned that situation may go out of control if the government used force against workers. He said that "two of the workers were injured at Rajmahal mines in ECL in lathicharge by the police while some were detained in Jharkhand." AICWF General Secretary Jibon Roy said, "Two parallel lines cannot meet" as the government is "hell-bent" to use force by deploying police forces at mines and inducting casual workers from outside. Meanwhile CPI(M) has also extended support to the striking workers. It said this strike in the coal sector is to protest against the ordinance promulgated by the government leading to "denationalisation" of coal mining in the country. "The Polit Bureau congratulates and greets the coal workers for building up total unity and for a successful strike, the party said demanding recall of the ordinance. The strike may lead to coal behemoth CIL missing its production target of 507 MT for the ongoing fiscal. "We are united and continue our strike on the second day," Indian National Mine Workers' Federation (INTUC) Secretary General S Q Zama told PTI, adding "we will continue with the strike till January 10." The strike, joined by all five major trade unions - BMS, INTUC, AITUC, CITU and HMS - is also likely to affect fuel supply to power plants. CIL accounts for over 80 per cent of domestic coal production. The CIL chairman, who had assumed charge only on Monday, had said he is hopeful that the situation would be resolved in an amicable manner.