Internet collective Anonymous has vowed to avenge of the arrest of three people in Spain who were suspected to be members of the group.

Anonymous didn’t say much.  All it did was post “V for Spain... We are Legion, so EXPECT US” on Twitter and “V For Spain Expect US.” on its blog.  Its blog post featured a red V, 
Spanish authorities said the three arrested individuals were suspected leaders of Anonymous members based in Spain. The individuals were suspected of coordinating the hacking of corporations, government websites (including those of the Spanish government), and specifically Sony’s PlayStation Network.

The police also claimed that one of the arrested Spaniard’s apartments contained a computer server that was used to hack Sony.

According to RTT, the arrest of the three Spanish members followed the detention of suspected Anonymous members in the US, UK, and Holland.

Anonymous is known for its politically motivated cyber attacks.  Most recently, it attacked government websites of Turkey to protest Internet censorship, government websites of Syria for “massive repression” and the abduction of a Syrian blogger, and the US Chamber of Commerce website for supporting the PROTECT IP Act.

Anonymous is also known for acts of vengeance.

Arguably the most infamous Anonymous attacks were against Amazon, PayPal, MasterCard, and Visa to punish their refusal to provide services to Wikileaks.