Hundreds of thousands of people marched on the streets of the Bangladeshi capital Wednesday carrying placards calling for alleged war criminals to be tried in special tribunals, witnesses said, according to dpa. The march was organized by political parties, human rights groups, students and cultural activists to mark the 37th anniversary of independence of the country that was carved out of former eastern Pakistan. The groups are demanding the trial of the extremist Muslim priests for allegedly masterminding mass killings in support of the occupying Pakistanis. Thousands of paramilitary frontier guards and police reservists secured strategic installations in Dhaka. The interim government also beefed up security in the southern port city of Chittagong, the country's business hub. Authorities said about 8,000 security forces were deployed for the anniversary. The high alert was in effect across Bangladesh because of threats from suspected militant Islamists vowing to disrupt independence celebrations. The militants are demanding Islamic rule in Muslim majority Bangladesh. The official celebrations began at dawn and was heralded by a 31- gun salute, a military parade with army, navy and air force contingents participating in more than an hour of fanfare. A a military hardware display included Russian-built Mig fighters and a customized South Korean frigate. For the first time in 37 years, a military delegation from neighbouring India was invited to witness the parade on the abandoned runway of an old airport near the army garrisons in Dhaka. The Indian military joined the war on behalf of the Bangladeshi freedom fighters playing a crucial role in the last days of the conflicts. March 26 marks the separation of Bangladesh, formerly East Pakistan, from Islamabad. Paramount leader Sheikh Mujib ur Rahman declared independence on March 26, 1971 and called on Bangladeshis to wage a war to drive out the occupying Pakistanis. The allied armies of Bangladesh and India forced the then Pakistani military junta to surrender on December 16, 1971 after nine months of a bitter war in which 3 million Bangladeshis - mostly civilians - were killed. More than 1,000 Indian soldiers were also killed in the Bangladesh war against Pakistan. Several million Bangladeshis fled to India to escape the brutality of Operation Searchlight carried out by the Pakistani military.