The eastern Indian state of West Bengal has plunged into a political crisis over Tuesday's attacks on its Chief Minister Mamata Banerjee and Finance Minister Amit Mitra by student activists of the state's main opposition Communist party in the national capital.

Members of the ruling Trinamul Congress party have ransacked several offices of the opposition Communist party across the state since Tuesday in retaliation against the alleged manhandling of the Chief Minister and Finance Minister by members of the Students ' Federation of India, the student-wing of the Communist Party of India (Marxist) which was in power in West Bengal for 34 years till 2011.

The demonstrators -- angry over the death of a 22-year-old student activist in police custody in state capital Kolkata last week, though cops claim he died after hitting a pole -- were caught on TV channels heckling the Chief Minister and beating up the Finance Minister as the duo were entering the Planning Commission office for a meeting.

Mitra has been admitted to a government hospital in the Indian capital with injuries.

Banerjee, who came to the Indian capital on Tuesday to attend a series of meetings with the central government, has cancelled all her meetings, including those with Prime Minister Manmohan Singh and Finance Minister P. Chidambaram, slated for Wednesday.

"Delhi is not safe. I was manhandled. When I tried to get down to the Planning Commission (office), the police did not cooperate at all," the Chief Minister and head of the regional Trinamul Congress party told the media while leaving for Kolkata.

West Bengal's Governor M.K. Narayanan has condemned the attacks, calling the incident "a blot on India's cherished democratic values". "The shocking pre-meditated assault on the Chief Minister, the Finance Minister and other senior ministers of West Bengal in the national capital is an extremely unfortunate incident," he said in a statement.

The Communist Party of India (Marxist) has also "disapproved of and condemned" the incident. "The party will look into how this has happened," a party statement said.

The Trinamul Congress party is an erstwhile ally of the country 's ruling Congress-led United Progressive Alliance, which withdrew its support last year over the central government's decision to allow foreign direct investment in retail sector.