The UK’s National Crime Agency said the suspect was held in West Sussex on Tuesday on suspicion of offences involving the misuse of computers and was released on conditional bail.

“Although this arrest is a positive step, the investigation into this incident is in its early stages and remains ongoing,” said Paul Foster, head of the NCA’s national cybercrime unit.

“Cybercrime is a persistent global threat that continues to cause significant disruption to the UK.”

Starting late on Friday and lasting through the weekend, airports in Berlin, Brussels and London were hit by disruptions to electronic systems that snarled up check-in and sent airline staffers trying options like handwriting boarding passes or using backup laptops. Many other European airports were unaffected.

The cyberattack affected the software of Collins Aerospace, whose systems help passengers check in, print boarding passes and bag tags, and dispatch their luggage.

The US-based company on Saturday cited a “cyber-related disruption” to its software at “select” airports in Europe.

It was not immediately clear who might be behind the cyberattack, but experts said it could turn out to be hackers, criminal organisations or state actors.

The European Commission, the executive branch of the 27-nation European Union, said aviation safety and air traffic control were unaffected.