Security forces went on high alert on Sunday (December 3) to avert trouble as Bangladesh was hit by a countrywide transport blockade -- the fourth in as many weeks -- amid a deepening political crisis ahead of elections in January. But what started peacefully, turned violent during the day. Clashes broke out between rival political activists across Bangladesh, in which one man was killed and 30 were injured. One man was killed and 30 were injured in the latest spate of violence. Witnesses said road links between the capital Dhaka and the port city of Chittagong, as well as other main cities, were paralysed as the blockade took hold early on Sunday, a working day in mainly Muslim Bangladesh. Few vehicles moved in Dhaka, where groups of chanting activists from a 14-party alliance led by Sheikh Hasina, head of the Awami League, gathered at key points. Riot police and paramilitary troops patrolled the streets and guarded key buildings in the city of 10 million people. Hasina's alliance said late on Saturday the blockade and other protests would be peaceful unless the police or rival political activists were resorting to any excess. The alliance demands a complete restructuring of the election commission, changes to the election schedule including the voting day the commission set for Jan. 21, and the resignation of President Iajuddin Ahmed as head of an interim government in charge of conducting the polls. Hasina and her main rival Begum Khaleda Zia of Bangladesh Nationalist Party (BNP) met the president and his council of advisers late on Saturday. But they failed to resolve the stalemate. Khaleda ended her five-year tenure as prime minister late in October, handing over power to a caretaker authority. The constitution dictates the election must be held within three months of the change over.