Computer hackers and virus spreaders could be jailed for five years in serious cases under new laws approved by European Union justice ministers today.
Authorities worldwide have woken up to the dangers of serious network failures in key installations such as electricity and water supply.
Since the September 11th, 2001 attacks, concerns have also grown about hackers gaining access to security information.
"There will be common definitions...and sanctions for a number of online criminal activities," European Commissioner for Justice and Home Affairs, Mr Antonio Vitorino, said.
The law seeks to harmonise existing national rules in the 15-nation European Union, where there are vast gaps in laws. It targets anyone who illegally enters a computer network or server.
It is also aimed against anyone who sends computer viruses such as the infamous "I love you" virus, which caused major information system breakdowns globally in 2000, as well as other types of destructive software such as "worms".
Hacking and spreading viruses, when committed by organised criminals, will be punished with jail terms of no less than two years - and up to five years - under the new law. Less serious offences could result in jail terms of between one and three years.
Many incidents of hacking are believed to go unreported by companies and government bodies due to the difficulty in tracking the culprits.
One industry hit by organised attacks is online gambling, where hackers have managed to crack servers, corrupt games and rack up winnings worth millions of dollars, according to industry and security experts.