Coimbatore, Sept 29 (PTI) Police on Thursday said they have received a letter threatening to hurl petrol bombs at 16 places in the nearby Pollachi town and that they have intensified the search. According to the police, they received a letter sent by post to a police station saying: "We are not against the police, but want to create law and order problem." The letter was sent allegedly in the name of SDPI and PFI, the police said. Three special teams have been formed for investigation and security has been beefed up and search stepped up, they said. On September 22, three PFI activists were held on charges of damaging two cars and two autorickshaws belonging to BJP and Hindu Munnani leaders in Pollachi. Multi-agency teams, spearheaded by the National Investigation Agency (NIA), had last week carried out raids on 93 locations in 15 States across the country and arrested over 100 PFI leaders for allegedly supporting terror activities in the country. PTI NVM NVG NVG