"Do not make the mistake of challenging Anonymous," the hacker collective declared in a stark message on its website yesterday. The message was a direct response to a NATO report that said Anonymous should be infiltrated and its members jailed. Spain responded to the verbal backhand by delivering Anonymous a not-so-subtle slap in return; today, Spanish police announced that they've arrested three "senior" members of the legion and seized a server that played a crucial in many recent Anonymous attacks, including the PlayStation Network take-down.

Spanish police began their investigation late last year after Anonymous targeted the Spanish Culture Ministry's websites in October. After Spain's Central Election Board was targeted by hackers in May, police dropped the hammer on the first subject, who was arrested in his home in the city of Almeria, the Wall Street Journal reports. Spanish police found a server in the home that helped to launch many of Anonymous' attacks in the past, including the Sony Playstation Store, the Spanish banks BBVA and Bankia, the Italian energy company ENEL and the governments of Egypt, Algeria, Libya, Iran, Chile, Colombia and New Zealand. Subsequent attacks resulted in the arrest of two other individuals and the confiscation of a computer that contained software "designed specifically to infect other people's computers."

Anonymous denied being behind the PSN attack, so it's interesting to hear the Spanish police say they've found evidence to the contrary. How do you think Anonymous will respond to the attacks? Trading blows with global governments is bound to end poorly for the group. "If you cut down one Anon, ten more will join us purely out of anger at your trampling of dissent," Anonymous' message warned; we'll see if crowds rush in to take the place of the arrested individuals.