Bangladesh was brought to a halt for the second time in a week on Sunday as a 36-hour nationwide opposition strike over changes in the electoral system began, amid tight security. Police said 9,000 policemen and 3,000 paramilitary Rapid Action Battalion (RAB) were deployed in the capital Dhaka after five vehicles, including three buses, were torched on Saturday, creating widespread panic. Shops, businesses and schools were shut on Sunday -- a weekday in the Muslim-majority nation -- and major roads and highways were deserted. The main opposition Bangladesh Nationalist Party (BNP) and its key Islamist ally, Jamaat-e-Islami, are enforcing the strike in protest against changes in the electoral system, which they say unfairly favour the incumbent government. Dhaka police spokesman Masud Ahmed said magistrates were deployed on the roads to tackle violence head-on. \"On Saturday night the magistrates sentenced 55 people to up to three months in jail for vandalism and torching vehicles,\" Ahmed said. Intelligence chief Colonel Ziaul Ahsan told AFP that paramilitary forces were patrolling Dhaka streets in vans but the situation was peaceful. The strike was called after from the ruling Awami League party announced plans last month to scrap a decades-old system under which a caretaker government takes over during election time. The system is designed to cover three months over each polls in Bangladesh, which has a long tradition of political violence since independence in 1971. BNP leader Khaleda Zia has said her right-of-centre party would not contest any future polls if the government scrapped the caretaker system, which oversaw four successive polls. Major Islamist parties have backed Zia\'s move. At least 2,000 policemen were deployed in the second biggest city of Chittagong where cargo delivery at the port, which handles 90 percent of the country\'s foreign trade, came to a halt, local police said. The strike is the fifth the BNP has called since it suffered a crushing defeat in December 2008 elections. A strike last Sunday saw protesters clash with police, leading to dozens of arrests.