Environmental group Greenpeace said on Wednesday it could halve its workforce in India to 30 early next year due to a block on its bank account after accusations of illegal donations.
The Centre has tightened scrutiny of non-profit groups over the past four years. The government 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.
The Enforcement Directorate froze Greenpeace's main bank account on October 5.
Greenpeace, which denies wrongdoing, said it only had funds to pay employees for about two more months, meaning half of the staff of 30 were at risk of losing their jobs.
"There are multi-pronged attacks on us," said Greenpeace spokesman Nandikesh Sivalingam, blaming the coal lobby.
"The coal industry is strong and powerful even if governments do want to move away from coal, including for climate change reasons."
It was not immediately possible to contact the Enforcement Directorate and a spokesman for the Finance Ministry, under which it operates, declined comment.
Asok Dasgupta, president of lobby group Independent Power Producers Association of India, said it was unfair to blame power producers for action against Greenpeace.
"I don't understand this opposition to coal," he told Reuters.
"Renewable power can't take over coal for many, many years. Fortunately we have got good coal reserves and we should use them."
Since PM Modi took office in 2014, India has cancelled registration 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.
In October, authorities froze the bank accounts of rights watchdog Amnesty International after a raid on its office. Amnesty regularly accuses the government of violations in Jammu and Kashmir.
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