A British man has been arrested on suspicion of launching a cyberattack on a German telecoms company, which left one million customers unable to go online.

Germany's federal police said the 29-year-old, whose name has not been released, was held on a European Arrest Warrant over the attack on a Deutsche Telekom internet access router in November.

He was picked up at Luton airport in a joint operation with Britain's National Crime Agency (NCA) on Wednesday.

The suspect planned to hack the router to integrate it into a networked "botnet" for cybercrimes, the German federal police said.

Prosecutors allege the man offered to sell the botnet over the so-called darknet for "attack scenarios like so-called DDoS attacks."


A DDoS, or "Distributed Denial of Service," attack involves trying to make an online service unavailable by overwhelming it with traffic from multiple sources.

Cologne public prosecutor Dr Daniel Vollmert said police were planning to extradite the man to Germany to face a charge of attempted computer sabotage.

"He is accused of being the mastermind behind the attack," the prosecutor said.

The Briton could face up to 10 years in jail if convicted.