The National Crime Agency has warned hackers they will be tracked down and brought to justice, after 28-year-old Lauri Love was charged with hacking into US government computer systems.
The NCA said: "Cyber-criminals should be aware that no matter where in the world you commit cyber crime, even from remote places, you can and will be identified and held accountable for your actions.
"The NCA has well-developed law enforcement alliances globally and we will pursue and deal robustly with cyber-criminals."
A Briton has been charged with hacking into computer systems of the US military, NASA and other federal agencies.
Lauri Love, 28, is accused of working with two other people in Australia and one in Sweden, who have not been charged, according to the Associated Press.
The US government said the purpose of the Briton's hacking was "to disrupt the operations and infrastructure" of the federal government.
A Briton has been charged with stealing a huge amount of confidential data from thousands of computer systems, including US military networks.
Lauri Love was charged with one count of accessing a US department or agency computer without permission and another charge of conspiracy.
The 28-year-old, who lives in Stradishall, Suffolk, allegedly hacked into networks including the US Department of Defense's Missile Defense Agency and the US Army Corps of Engineers.
Mr Love allegedly accessed information including budgeting data and personal information on thousands of people including military personnel.
He was arrested on Friday by authorities including the UK's National Crime Agency in a separate investigation.