Hackers targeted Collins Aerospace systems, causing chaos at Heathrow, Berlin, and BrusselsA ransomware attack was behind the airport disruptions that crippled automated check-in systems in some of Europe's busiest hubs over the weekend, media reported on Monday, citing the EU's cybersecurity agency ENISA. "The type of ransomware has been identified. Law enforcement is involved to investigate," ENISA said in a statement, as quoted by Reuters, without specifying where the attack originated from. Reuters quoted Collins Aerospace as saying on Monday that it was working with the affected airports and was in the final stages of completing updates to help restore full functionality. Ransomware is a type of malicious software that blocks access to a computer system or data, usually by encrypting them, until the victim pays a ransom.