The technology, called an IMSI catcher, also allows for phone calls to be intercepted and listened to. Text messages and emails can also be collected and read. Additionally, it can block phone signals in a specific area.
But it's not just the suspect's phone which is taken under control by the technology; all active mobile phones in the area are. Sources in the Metropolitan Police told The Times that the data of innocent people may also be stored in archives .... http://rt.com/uk