A cyber attack against Polish flagship carrier LOT grounded more than 1,400 passengers at Warsaw's Frederic Chopin Airport on Sunday, a spokesman said.
The attack occurred at around 4:00 pm local time (1500 GMT), and targeted the airline's ground operations system, it said in a statement.
The incident, which led to the cancellation of 10 flights departing from Warsaw, was resolved by 9:00 pm.
"This is the first attack of its kind," LOT spokesman Adrian Kubicki told TVN 24 television.
The airline said in a statement on its website that the "IT attack" meant it was unable to create flight plans and flights were not able to depart from Warsaw.
Poland's security agencies were investigating the attack.