The NRC, to be published on July 30, is only a draft and after its publication, adequate opportunities for filing claims and objections will be available to those whose names are excluded from it, he added.
"All claims and objections will be duly examined. The NRC authorities will give a one-month window, when all objections and complaints will be examined after giving a proper hearing to the complainants. Only thereafter, the final NRC will be published," the official said.
Exclusion from the final NRC does not mean automatic declaration of anyone as foreigner and once the final document is published, if someone is dissatisfied, he or she can always go to a foreigners' tribunal in the state to get justice, he added.
There are around 300 foreigners' tribunals in Assam.
The official said no one should have any apprehension about the exercise and added that adequate central paramilitary forces were dispatched to Assam to assist the state administration to deal with any law-and-order situation.
On Sunday, Union Home Minister Rajnath Singh had said there was no need to panic and all bona fide Indians will be given adequate opportunities to prove their citizenship.
He had also said the NRC was being updated in accordance with the 'Assam Accord' signed on August 15, 1985 and the process was being carried out as per the directions of the Supreme Court, which was monitoring it continuously.
The home minister had asserted that the NRC exercise was being carried out in a totally impartial, transparent and meticulous manner and will continue so.
The part draft of the NRC was published on the intervening night of December 31 and January 1, wherein the names of 1.9 crore of the 3.29 crore applicants were incorporated.
On July 30, the fate of all 3.29 crore applicants will be decided.
The massive exercise, aimed at identifying the illegal immigrants in the north-eastern state bordering Bangladesh, is being carried out following a decision in 2005 after a series of meetings involving the central and state governments and the influential All Assam Students' Union (AASU).
When the NRC was first prepared in Assam in 1951, the state had 80 lakh citizens.
The process of identification of illegal immigrants in Assam has been debated and has become a contentious issue in the state's politics.
A six-year agitation demanding identification and deportation of illegal immigrants was launched by the AASU in 1979.
It had culminated with the signing of the Assam Accord on August 15, 1985, in the presence of the then prime minister Rajiv Gandhi.
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