The Tamil Nadu’s Bharatiya Janata Party unit on Saturday demanded that the state government order a judicial probe into the murder of its general secretary and gave a call for a statewide bandh on July 22, even as special police teams were formed to track down the assailants.A four-member unidentified gang hacked to death state unit BJP’s general secretary V Ramesh, 52, while he was returning home after visiting the party office on Friday night in Salem. As a precautionary measure, authorities ordered closure of schools in Salem today. "We want the guilty to be brought to book. We want a detailed probe into the incident by a retired judge of the Madras high court," said BJP state President Pon Radhakrishnan. "We want a detailed probe so that such incidents don't happen in the future," he said. Radhakrishnan accused the state government of not providing security to his party leaders and claimed in the last one year, three state-level leaders -- Arun Reddy, P Murugan and Velliyan -- had been murdered and the culprits were still at large. He alleged that even police had not taken action on their pleas to provide protection to party members. BJP's national leaders condemned the incident, with Gujarat Chief Minister Narendra Modi and Leader of Opposition in the Lok Sabha Sushma Swaraj calling for action against the guilty. Both expressed shock over Ramesh's killing, with Swaraj pointing out that this was the third such incident in the state involving a senior party functionary. "Killing of our Tamil Nadu unit's General Secretary Ramesh is shocking. Spoke to TN BJP President last night and expressed sadness on the killing. My deepest condolences to the family of Ramesh. May his soul rest in peace. The culprits must be punished at the earliest," tweeted Modi. Swaraj said the government must apprehend those behind the "brutal" murder. National spokesperson Nirmala Seetharaman said BJP leaders in the state were being attacked in a "planned manner". She demanded that the state government set up a Special Investigation Team to probe each of the attacks on party leaders in the state. Anguished over the killing, BJP activists staged protests in Chennai, demanding immediate arrest of those responsible for the murder. Salem range Police Deputy Inspector general Sanjay Kumar said the BJP leader had gone to his office to discuss party affairs around 9 pm and was attacked by four people while returning to his residence. Meanwhile, Janata Party President Subramanian Swamy demanded that the state government appoint a Special Investigation Team to probe the recent killings of leaders of Hindu outfits. A report from Coimbatore said tight security cover has been thrown in and around the city today, following the murder of Ramesh. More than 50 per cent shops and commercial establishments were closed in nearby Tirupur. Nearly 1,000 police personnel were posted to keep vigil in sensitive areas and 33 patrol vehicles were also deployed, police said. Similarly, closure of shops were also reported in Avanashi and Palladam, and some BJP workers were arrested for trying to block roads in Tirupur district. In Kumbakonam, 13 BJP workers were taken into custody for staging a demonstration.