Pakistani authorities today said they had traced a gang of hackers and arrested five suspects involved in defacing thousands of domestic and international websites and online fraud.

The "internationally-known hackers" have been picked up in an operation spanning the country over the past few weeks, Federal Investigation Agency (FIA) senior officer Mian Idrees said.

"We have unearthed notorious hackers' group 'Pakbugs' and arrested five members of this group," he said.

Authorities seized computers and other equipment involved in various cyber crimes, he said.

The FIA said in a statement the group was involved in hacking or defacing thousands of websites belonging to government, non-government and international organisations.

"They were also involved in credit card jacking and usage of stolen credit cards," it said.

"Pakbugs" founder Jawad Ehsan, alias Humza, remains at large and is believed to be based in Saudi Arabia, the statement said.

But it said co-founder Hassan Khan has been detained in the northwest Pakistani city of Peshawar, along with other members in Lahore, Bannu and Rawalpindi.

Idrees ruled out the hackers' involvement in terrorism and said the men had been charged only with electronic crimes.

Pakistan, fighting terrorism and high-tech offences, in 2008 declared cyber-terrorism a capital crime, while electronic fraud is punishable by a prison term of seven to ten years.