Chandigarh, April 29 : Curfew was clamped in Punjab's Patiala's town on Friday after police had to fire into the air following a massive clash between members of the Shiv Sena led by Harish Singla and pro-Khalistan sword-bearing sympathizers outside the Kali Mata temple, who were pelting stones at each other and brandishing swords, police said. Inspector General of Police, Patiala Range, Rakesh Aggarwal told the media the situation was under control and heavy police deployed. "The tension started following rumours that some of the protesters had been attacked," he said. Eyewitnesses told the police that Nihangs, who gathered in front of the Dukh Niwaran Sahib gurdwara to oppose the Khalistan 'Murdabad March' of the Shiv Sena, marched towards the temple, raising pro-Khalistan slogans. A police officer got injuries while trying to stop the Nihangs heading towards the temple, the police said. Terming the incident of clashes as highly deplorable and extremely unfortunate that needs to be condemned by one and all in the strictest possible words, Chief Minister Bhagwant Mann appealed to the people to maintain law and order at all costs besides upholding the long traditional love, peace, brotherhood, and harmony. Expressing anguish, he called upon the people to extend fulsome support and cooperation to the police and civil authorities by exercising restraint in this hour of crisis. He categorically said no one would be allowed to disturb the hard earned peace and communal harmony in the state. "The incident of clashes in Patiala is deeply unfortunate. I spoke with the DGP, peace has been restored in the area. We are closely monitoring the situation and will not let anyone create disturbance in the State. Punjab's peace and harmony is of utmost importance," Mann tweeted. Reiterating his government's firm commitment, he said: "Nothing should be done to disturb the peaceful atmosphere as we are all morally committed to make Punjab the most peaceful, harmonious and prosperous state in the country." As a preventive measure, a curfew has been imposed till Saturday morning. Singla, the executive president of the Shiv Sena, led the anti-separatist march from Arya Samaj Chowk to Kali Devi Temple. They were raining slogans against Khalistan. "The Shiv Sena will never allow Khalistan to be formed in Punjab or anywhere in India," said Singla. He also said banned Sikhs For Justice (SFJ) chief Gurpatwant Singh Pannu had given the call to mark the foundation day of Khalistan on April 29. Responding to the clash, Congress leader Rahul Gandhi advised the AAP government that peace and harmony are most imperative in a sensitive border state. "Punjab is not the place to carry out experiments." Former Chief Minister Amarinder Singh said: "Concerned about the tense situation arising due to clashes between two groups in Patiala. People of Patiala are peace loving and I appeal to them not to get provoked. Hope that Punjab Police will take firm action and ensure that law and order is maintained." BJP leader Harjeet Singh Grewal said action should be taken against both sides. /IANS