Spain and three South American countries arrested 25 suspected hackers associated with the Anonymous activist group today on accusations of defacing government and corporate websites, officials said.
Spanish police also accused one of four suspects picked up in the cities of Madrid and Malaga of releasing personal data about police officers and bodyguards protecting Spain's royal family and the prime minister.
Other arrests were in Argentina, Chile and Colombia, and 250 items of computer equipment and mobile phones were seized across 15 cities, Interpol said.
Colombia's ministry of defence and presidential websites as well as Chile's Endesa electricity company were among the targets of the hackers, it said.
The loosely organised group Anonymous is suspected of coordinated computer hacking against institutions, multinationals and government organisations across the world.
"These cyber attacks were sometimes individual actions but they were supported by many people who joined forces and knowledge to commit them," Spanish police said in a statement released by the interior ministry.
"Those arrested ... had a high level of knowledge of information technology.
"Earlier this month, anti-secrecy group WikiLeaks began publishing more than 5 million emails from US-based global security analysis company Stratfor believed to have been obtained by Anonymous supporters.
In Spain, two of the four suspects remained in custody while the other two, including a 16-year-old, were released on bail by a court, police said.
The Spanish police accused the suspects of tampering with the websites of political parties, for example by putting fangs on images of party leaders. Spanish companies were also targeted, the police said.
The group had set up a chat-room to help run computer attacks in Spain and Latin America.
After the arrests, a call went out in chat-rooms affiliated with the suspects for supporters to attack the Spanish police website. The petition specifically asked for people from outside of Spain to carry out the attacks "so that the police would not have enough data to lead to new arrests", according to the statement.
In June, Spanish police arrested three suspected Anonymous members on charges of cyber attacks against targets including Sony's PlayStation store, governments, businesses and banks.
Reuters