In March 1929, 31 labour leaders were arrested on the charge of conspiracy. The leaders included three Englishmen who had helped in the organization of the workers movement in India. They were taken to Meerut and were tried. The trial lasted for four years and is known as Meerut Conspiracy Case. Many defense committees were formed all over the country and even in England and other foreign countries. The nationalist leaders provided legal defense to the accused. Some of them were acquitted while others were convicted. The workers organizations had been growing and played an active part in the nationalist movement. The British government issued the Public Safety Ordinance in 1929 to remove from India persons it considered British and foreign communist agents.