Cyber crook Paul Dixon has admitted targeting websites belonging to two police forces and British Airways.
Dixon carried out ‘denial of service’ attacks on sites including Durham Constabulary and Police Scotland in the space of a few days.
His illegal behaviour meant the websites were unavailable for people to use.
The 23-year-old pleaded guilty to five offences under the Computer Misuse Act during a brief appearance at Newcastle Crown Court.
He will be sentenced next month and was released on conditional bail until then.
The case was investigated by officers from the cyber crime unit based in NERSOU (North East Regional Special Operations Unit).
After Dixon entered his guilty pleas, DC Greg Hodgson said: “This is a serious crime which has severe consequences to those companies and services who are targeted.
Full details of the offences were not revealed and Judge Stephen Earl adjourned sentence until May 4 and asked for a pre-sentence report to help determine what the punishment should be.
The judge said “custody is a realistic prospect” but that he wanted an “all options” report.
Sam Faulks, for Dixon, said: “This defendant is of hitherto good character, he would welcome a pre-sentence report.”