Spy agencies are caught in a "technology arms race" with terrorists and criminals, the new head of Britain's MI6 said on Monday in his first public comments since becoming chief.
Alex Younger defended the use of data by the Secret Intelligence Service, known as MI6, after the release of documents by former CIA contractor Edward Snowden sparked criticism of sweeping mass surveillance by intelligence agencies.
"Using data appropriately and proportionately offers us a priceless opportunity to be even more deliberate and targeted in what we do, and so to be better at protecting our agents and this country," Younger said.
"The bad news is the same technology in opposition hands, an opposition often unconstrained by consideration of ethics and law, allows them to see what we are doing and to put our people and agents at risk," he said.
"So we find ourselves in a technology arms race."