DHAKA (AFP) - Authorities in Bangladesh have arrested more than 250 political activists from the country's two main parties in a new nationwide wave of arrests, the parties said Sunday. The arrests came days after the Awami League of Sheikh Hasina Wajed and the Bangladesh Nationalist Party of Khaleda Zia said they would boycott talks with the army-backed administration on organising elections in December. Police officials confirmed arrests had been made as part of a special nationwide crackdown, but denied they were political and did not say how many people were being held. "We are arresting people against whom there are specific cases of crime. It is part of a month-long special crackdown on criminals," national police chief Nur Mohammad told AFP. "It has nothing to do with harassing people or any political parties." The BNP and the Awami League said at least 250 of their members have been arrested since late Friday. The Bengali-language daily Prothom Alo put the number at 258. "The government have targeted our activists and district leaders throughout the country. They want to harass us to create an atmosphere of fear and panic," said BNP spokesman Rizvi Ahmed.Senior Awami League official Amir Hossain Amu said the arrests were "politically motivated." "The government should stop political repression in the country," he said. The military-backed government, which came to power in January 2007 after emergency rule was imposed and elections cancelled, has already detained thousands of party activists in a bid to clean-up the country's graft-ridden politics. More than 150 top politicians including Sheikh Hasina and Zia - the two ex-premiers who lead the two sidelined parties - have been arrested during the drive while dozens of former ministers and ex-lawmakers have been jailed for up to 20 years. Both main parties say they will take part in talks to restore democracy only if their leaders are released. A Bangladesh court earlier this month charged Sheikh Hasina with taking bribes. Her bitter rival Zia is being held on charges of graft linked to the awarding of a multi-million-dollar government contract.