The tea-rich state of Assam has long been the centre of social and communal tensions with locals campaigning against illegal immigrants

MUMBAI, July 30 (Reuters) - India said on Monday it had excluded more than 4 million people from a draft list of citizens in the border state of Assam who could not produce valid documents, a move that has sparked fears about the future of thousands in the region.

Security has been tightened across the state, which borders Bangladesh, as thousands of Bengali-speaking Muslims worry about being sent to detention centres or deported, a Reuters witness said.

The tea-rich state of Assam has long been the centre of social and communal tensions with locals campaigning against illegal immigrants, a fight that Prime Minister Narendra Modi's Hindu nationalist-led government has championed.

In 1983, scores of people were chased down and killed by machete-armed mobs intent on hounding out Muslim immigrants.

The government said the draft was not meant to drive people out and those struck out of the list would have a chance to re-apply.

"Based on this draft, there is no question of anyone being taken to detention centres or foreigners' tribunal," Sailesh, India's census commissioner who uses only one name, told rerporters in Guwahati, the state's main city.

Hundreds of thousands of people fled to India from Bangladesh during Bangladesh's war of independence from Pakistan in the early 1970s. Most of them settled in Assam, which has a near-270 km (165-mile) border with Bangladesh.

More than 30 million people had applied and 4,007,707 had been excluded from the list, Sailesh said.

To be recognised as Indian citizens, all residents of Assam had to produce documents proving that they or their families lived in the country before March 24, 1971.

Sailesh did not provide a breakup of people who had failed to make to the draft list.

Critics see the citizenship test as another measure supported by Modi's Bharatiya Janata Party (BJP) aimed at minority Muslims. The BJP denies any bias but says it opposes a policy of appeasement of any community.

Authorities in the state have previously said the citizenship test was crucial to protect ethnic Assamese, many of whom have demanded removal of outsiders they accuse of taking jobs and cornering resources in the state of 33 million.

The first draft of the National Register of Citizens (NRC), released on Dec. 31, confirmed the citizenship of 19 million people, leading to jubilation for some and heartbreak among others.

The NRC, however, told the Supreme Court this month that 150,000 people from the first list, a third of them married women, would be dropped from the next one, mainly because they provided false information or gave inadmissible documents.

"If the government has decided to brand us foreigners what can we do?" said Abdul Suban, 60, a Bengali-speaking Muslim, earlier.

"The NRC is trying to finish us off. Our people have died here, but we will not leave this place." (Writing by Zeba Siddiqui in Mumbai; Editing by Sanjeev Miglani and Nick Macfie)

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