Could Russia and West be heading for cyber-war?
The latest warning of Russian intrusions is another sign that cyber-space is becoming one of the focal points for growing tension between Russia and the West.
But so far, much of the talk about cyber-war remains hypothetical rather than real.
It is true that Britain's National Cyber Security Centre (NCSC) is on high alert for the possibility of some kind of Russian activity. More people and resources have been devoted to monitoring and investigation.