A website run by a LockBit, a prolific ransomware syndicate behind cyber attacks around the world, has been taken over by law enforcement agencies.

The front page of LockBit’s site was replaced on Tuesday with the words “this site is now under control of law enforcement” alongside the flags of the UK, the US and several other nations.

The message said the website was under the control of the UK’s National Crime Agency “working in close co-operation with the FBI and the international law enforcement task force, Operation Cronos”.

It said it was an “ongoing and developing operation” that also involves agencies from Germany, France, Japan, Australia, New Zealand and Canada, among others, including Europol.

Tweet from @NCA_UK

LockBit, which has been operating since 2019, has been the most prolific ransomware syndicate two years running.

The group accounted for 23 per cent of the nearly 4000 attacks globally last year in which ransomware gangs posted data stolen from victims to extort payment, according to the cybersecurity firm Palo Alto Networks.

The group provides ransomware as a service to so-called affiliates, who infect victim networks with the computer-crippling malware and negotiate ransoms.

Last June, US federal agencies released an advisory that attributed about 1700 ransomware attacks in the United States since 2020 to LockBit and said victims included “municipal governments, county governments, public higher education and K-12 schools, and emergency services”.

Tweet from @FBI

Ransomware is the costliest and most disruptive form of cyber crime, crippling local governments, court systems, hospitals and schools as well as businesses.

It is difficult to combat as most gangs are based in former Soviet states and out of reach of Western justice.

Law enforcement agencies have scored some recent successes against ransomware gangs, most notably the FBI’s operation against the Hive syndicate. But the criminals regroup and rebrand.

Britain’s National Cyber Security Centre has previously warned that ransomware remains one of the biggest cyber threats facing the UK, and urges people and organisations not to pay ransoms if they are targeted.