Today, around 4p.m. (local time) the hackers attacked (ground) IT systems of Polish Airlines, LOT. They attacked a planning system without affecting the planes' systems.
If the attack was sponsored by Russia, would that be an act of war?
The Guardian: Hackers ground 1,400 passengers at Warsaw in attack on airline's computers
ABC Online: Hackers ground 1400 LOT passengers at Warsaw airport
Business Standard: Polish airline cancels flights after hacker attack
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