During a 1990 visit of Gorbachev to Vilnius, capital of Lithuania, about 250,000 persons protested in a public meeting. On 11th March 1990, leaders of Lithuania declared its independence from the Soviet Union. However, the Soviet central-government demanded Lithuania to give up its independence and sent the Soviet Army continued to keep many troops in Lithuania. The government said that it would have to follow the Soviet constitution if it wanted to leave. The Soviet Union also did economic blockade of Lithuania. Estonia and Latvia were also illegally taken by the Soviet Union in 1940. On 30th March 1990, the leaders of Estonia declared that the control of their country by the Soviet Union from 1940 was illegal. They also declared independence. The leaders of Latvia also started process of independence on 4th May 1990.