The issue has been linked to a cyberattack on the services provider, according to several media reports. London's Heathrow, as well as airports in Berlin and Brussels, were among those affected. Brussels airport also warned that flight delays and cancellations are expected on Monday as well. The airports warned passengers about longer waiting times and urged them to check their flight status in advance. Collins Aerospace was hit by ransom-seeking hackers in 2023, Reuters reported, citing several breach-hacking websites.