A US government report released on Friday shows the National Security Agency (NSA) collected over 534 million US phone records in 2017.
The agency used its powers to seize metadata from domestic phone calls and text messages, the report from the Office of the Director of National Intelligence said.
The metadata did not reveal the contents of phone calls but did allow the NSA to spy on who people call, when and for how long, as well as the amount of characters used in text messages.
Metadata is supposed to be anonymous, however it can be used to identify individuals, as a Stanford lawyer found in 2013.
This is done by pairing the metadata with publicly available social media information along with other sources.
The number of phone records obtained by the NSA last year was triple that accessed in 2016, Gizmodo reported.
