India's home ministry has blacklisted more than 800 non-governmental organisations (NGOs) in the country's north-east for alleged links with separatist groups.
By Subir Bhaumik
BBC correspondent in Calcutta
The move follows a drive by the government and intelligence agencies to trace the funding that rebels receive.
A senior home ministry official said a list of the NGOs had been given to all state governments in the region with a request to keep them under close watch.
The official told the BBC the government had solid evidence of close links between the NGOs and rebels.
Delhi had been concerned at the proliferation of NGOs in the region, the official said.
He said most were of dubious origin and served as a conduit for rebel funding both from foreign sources and government development money.
Meghalaya, a state of only around 2.5m people, has more than 8,000 NGOs.
Rebel groups operate in a number of north-eastern hotspots
They received nearly 1.5bn rupees ($32.2m) from the government last year out of the five billion rupees pumped into the state by Delhi.
More than 300 of the blacklisted NGOs are in Meghalaya.
Rebel groups there have stepped up their campaign of violence in recent months after long being dormant.
The home ministry official said state governments should take legal action against the blacklisted NGOs under anti-terrorism laws once they had sufficient evidence.
The minister for the north-east, CP Thakur, said recently that a large part of federal development funding for the region was finding its way to the rebel groups because corrupt politicians and bureaucrats were helping them siphon it off.
But analysts say that since many of these NGOs belong to minority religious groups such as Muslims and Christians, any strong action against them may lead to an outcry.
India's north-east has many hot spots where separatists are fighting government rule, including Nagaland, Meghalaya, Tripura and Assam.