At least 50 persons were injured on Sunday morning as clashes erupted after an unruly mob torched the district magistrate's (DM) office in south Kashmir's Shopian district.Tension gripped Shopian town after security forces intervened to stop a pro-freedom rally in Pinjura village.Demonstrators gathered in large numbers as the local mosques on loudspeakers asked people to join the protests.The protesters later torched the mini secretariat in Shopian town that comprises the office of the DM and many other district level officers.No employee was present at the secretariat when the incident occurred.Over four dozen people including protesters as well as security men were injured in clashes when the security forces tried to prevent the demonstrators from torching the building.Meanwhile, Home Minister Rajnath Singh who arrives here on Sunday leading the 28-member all party delegation to Kashmir, tweeted: "Heading to Srinagar with the all party delegation. We intend to talk to individuals and groups who want peace and normalcy in Kashmir Valley."The delegation will review the ground situation in the valley to explore ways and means to end the ongoing violence in which 74 people have been killed and thousands injured since July 9, a day after top militant, Burhan wani, was killed in a gunfight with the security forces.