Hundreds of people were left stranded outside Brussels' Zaventem International Airport after it suffered a power outage on 15 June.
Though power has since been restored, the disruption in flight schedules has caused many delays, local media reports said.
Passengers reportedly complained about being left in total darkness when the outage took place.
According to reports, the flight registration system was apparently down.
Power outage update: Systems are running again but delays are expected throughout the day. More info: https://t.co/tWqbWwVvQn— Brussels Airport (@BrusselsAirport) June 15, 2017
The ISIS suicide bombers had targeted the Brussels airport along with Maalbeek metro station in March last year in which 32 people were killed and more than 320 injured.