Lahore, May 25 : As PTI workers and leaders march towards Islamabad from various parts of the country, the police are on high alert as the government is taking all possible measures to stop the 'Azadi March', Geo News reported. At Lahore's Batti Chowk, the police resorted to tear gas shelling to disperse the PTI workers when they removed barriers placed to block the routes. The PTI's Lahore chapter had asked its workers to gather at the Batti Chowk on Wednesday from where they were to depart for Islamabad. The party workers gathered at the intersection and clashed with the police when they removed barriers after which the police fired tear gas shells in order to clear the area, Geo News reported. Meanwhile, taking to his Twitter handle, former energy minister Hammad Azhar announced that he has reached Batti Chowk. The police also encircled the car of former health minister Yasmeen Rashid in an attempt to stop her from moving forward. According to the video circulating on social media, a PTI supporter came forward and verbally abused the police officials. Meanwhile, Yasmeen tried stopping the police from taking away her car keys. /IANS