On Friday, a British hacker behind the Liberia cyber-attack of 2015-16, Daniel Kaye has been jailed for almost three years. The Blackfriars Crown Court in central London sentenced him to two years and eight months in prison, as Judge Alexander Milne QC said he had committed a “cynical” financial crime.

In October 2015, Kaye had launched a series of attacks an African cell phone operator, Lonestar. The attacks became so powerful that they inadvertently crashed the internet in Liberia the following year.

In a statement, Britain’s National Crime Agency (NCA) said that the 30-year-old was hired by a senior employee at a rival operator, Cellcom, to carry out the attacks. However, there is no indication that Cellcom was aware of the crime.

Last month, Kaye pleaded guilty to creating and using a botnet — a series of computers connected in order to attack systems — and of possessing criminal property.

The British hacker used a botnet, which he had created to set off repeated distributed denial of service (DDoS) requests on Lonestar, while he was living in Cyprus. In remedial action, the Liberian company spent nearly $600,000.

The NCA added that the company had to incur additional revenue loses of tens of millions of dollars, as the customers increasingly began leaving the network.

According to the agency, thus far, Kaye is perhaps the most significant cyber criminal caught in the United Kingdom.

The British hacker was arrested in February 2017, after which he was extradited to Germany. According to the media reports, Kaye admitted to the attacks on Deutsche Telekom that affected nearly 1 million users in November 2016.

The Head of Operations at the NCA’s National Cyber Crime Unit, Mike Hulett said, “Daniel Kaye was operating as a highly skilled and capable hacker-for-hire.”

“His activities inflicted substantial damage on numerous businesses in countries around the world, demonstrating the borderless nature of cyber crime,” he added. “The victims in this instance suffered losses of tens of millions of dollars and had to spend a large amount on mitigating action.”

Although Kaye has been jailed for the cyber-attacks in Liberia, he still is a suspect of the major international investigation into hundreds of acts of cyber sabotage across the world.