Press TV reports.
According to a report from the Wall Street Journal, US Attorney General Eric Holder gave the NCTC additional powers to store files on the Americans, even if they are not suspected of any crime.
The report says that Holder had allowed data mining -- a process focusing on extracting information from data - of entire government databases, earlier this year.
Flight records and information on American families hosting foreign students were reportedly among the material recorded. The material would be allowed to be held for up to five years.
Under the order of the attorney general, databases would be allowed to be shared with the governments of other countries in case an individual was suspected of a crime.
The move by the administration of US President Barack Obama follows failed attempts by former President George W. Bush to implement similar regulations.
Revisions to the NCTC, allowing confidential information to be collected, stored and analyzed for five years, were approved despite resistance from the Department of Homeland Security.
Groups such as the American Civil Liberties Union are protesting against the changes to the NCTC.
Reports say US authorities have granted the National Counterterrorism Center (NCTC) new powers in order to keep a closer watch on American citizens,