A man has been arrested on suspicion of launching attacks over the internet after an operation between Scottish police and the US Secret Service.
Denial of service attacks use "zombie" computers
A number of houses were searched in the Elgin area of north east Scotland on Friday and computers seized.
Officers were investigating attacks in which compromised computers - known as zombies - are used to flood websites with useless traffic.
A 27-year-old from Elgin is due to appear in court in the town on Monday.
The searches were carried out by officers from the Scottish Drug Enforcement Agency's (SDEA) National Hi-Tech Crime Unit.
They were part of Operation Casper, a joint investigation which has concentrated on what are known as "denial of service attacks".
A spokesman for the SDEA said these typically used hundreds of "compromised" computers to launch attacks.
"Over the past year we have seen a considerable rise in this type of attack, some of which also form the basis for extortion attacks," the SDEA said.
Its crime co-ordinator, Detective Chief Superintendent Stephen Ward, said: "Operation Casper has involved the SDEA working closely with the US Secret Service and is an excellent example of how law enforcement agencies, working together, can impact on internet-related crime.
"Business groups, organisations and individuals can all be subject of internet criminality and I would like to reiterate this agency's commitment to police this criminal behaviour in all its guises.
"The internet does offer criminals new ways of committing crime but it also offers investigative opportunities to law enforcement that the SDEA will continue to exploit."