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US and UK to stage 'cyber war' games to improve security

David Cameron and President Obama are to announce plans for British and US intelligence and security agencies to work together to tackle cyber attacks.

Agents in "cells" in both countries will stage war games to test the resilience of computer networks.

The measures come in the wake of recent cyber attacks on Sony Pictures and US Central Command.

Naomi Grimley reports from Washington.

  • 16 Jan 2015