NSA 'tracking' millions of mobile phones
Almost five billion mobile phone location records are logged by the NSA every day, according to the Washington Post.
Citing documents leaked by the former intelligence analyst Edward Snowden, the newspaper says the information can be used to track people's movements and chart their relationships.
The BBC's technology reporter Jane Wakefield spoke to Jon Sopel about how this affects people.
05 Dec 2013
- From the section US & Canada