NEW DELHI (Reuters) - Environmental group Greenpeace said on Saturday it had been forced to shut two of its regional offices in India and had asked many staff to leave due to a block on its bank account after accusations of illegal donations.

Prime Minister Narendra Modi’s nationalist government has tightened scrutiny of non-profit groups over the past four years. It says they often act against India’s interests and has revoked licenses for thousands of foreign-funded groups.

Known for its campaigns against India’s coal-fired power plants, Greenpeace has been barred from receiving foreign donations since 2015. India’s financial crime investigating agency froze the group’s main bank account on Oct. 5.

On Saturday, the group said 40 of its 60 India staff positions had been made redundant. Two of its regional offices -- in the capital city of New Delhi and the eastern city of Patna -- have been shut, it said in a statement.

Greenpeace staff across New Delhi and Patna, as well as in southern city Bengaluru, were committed to work as volunteers, the group said.

“The government can only freeze our accounts and shut our offices but Greenpeace is an idea that can never be extinguished,” it said.

Since Modi took office in 2014, India has canceled the registrations of nearly 15,000 non-governmental groups under the Foreign Contribution Regulation Act.

Critics say the government has been using the foreign funding law as a tool to silence non-profit groups which have raised concerns about the social costs of India’s rapid economic development or questioned its human rights record.