Activists of the mainstream political parties - BJP, SP and Congress- today staged demonstrations to protest the serial blasts in Mumbai.The district unit of BJP staged demonstrations at the district collectorate premises and flayed the government for withdrawing the Prevention of Terrorism Act (POTA) "leading to a spate of terror attacks in the country during the 2-year misrule of the UPA government".They demanded enactment of a stringent legislation for sternly dealing with the terrorists and their outfits. The SP youth brigade workers shouted slogans against the UPA government for its "failure" to tackle terrorism across the country.Workers form the Youth Congress also took out protest marches in various parts of the city and shouted slogans condemning the terror attacks.