A Dutch citizen arrested in northeast Spain on suspicion of launching what is described as the biggest cyberattack in Internet history operated from a bunker and had a van capable of hacking into networks anywhere in the country, officials said Sunday. 
  
 The suspect traveled in Spain using his van "as a mobile computing office, equipped with various antennas to scan frequencies," an Interior Ministry statement said. 
  
 Agents arrested him Thursday in the city of Granollers, 35 kilometers (22 miles) north of Barcelona, complying with a European arrest warrant issued by Dutch authorities. 
  
 He is accused of attacking the Swiss-British anti-spam watchdog group Spamhaus whose main task is to halt ads for counterfeit Viagra and bogus weight-loss pills reaching the world's inboxes. 
  
 The statement said officers uncovered the computer hacker's bunker, "from where he even did interviews with different international media." 
  
 The 35-year-old, whose birthplace was given as the western Dutch city of Alkmaar, was identified only by his initials: S.K. 
  
 The statement said the suspect called himself a diplomat belonging to the "Telecommunications and Foreign Affairs Ministry of the Republic of Cyberbunker." 
  
 Spanish police were alerted in March by Dutch authorities of large denial-of-service attacks being launched from Spain that were affecting Internet servers in the Netherlands, United Kingdom and the U.S. These attacks culminated with a major onslaught on Spamhaus. 
  
 The Netherlands National Prosecution Office described them as "unprecedentedly serious attacks on the nonprofit organization Spamhaus." 
  
 The largest assault clocked in at 300 billion bits per second, according to San Francisco-based CloudFlare Inc., which Spamhaus enlisted to help it weather the onslaught. 
  
 Denial-of-service attacks overwhelm a server with traffic, jamming it with incoming messages. Security experts measure the attacks in bits of data per second. Recent cyberattacks _ such as the ones that caused persistent outages at U.S. banking sites late last year _ have tended to peak at 100 billion bits per second, one third the size of that experienced by Spamhaus. 
  
 Netherlands, German, British and U.S. police forces took part in the investigation leading to the arrest, Spain said. 
  
 The suspect is expected to be extradited from Spain to face justice in the Netherlands. ||||| Story highlights Police say the suspect traveled around Spain in a van he used as a mobile office 
  
 He was arrested at the request of judicial authorities in the Netherlands 
  
 Spanish police say the 35-year-old was behind a massive cyberattack last month 
  
 The suspect, a 35-year-old Dutch citizen, traveled around Spain in a van he used as a mobile office, Spain's National Police said in a statement Sunday. 
  
 Police arrested him Thursday north of Barcelona, Spain, on a European arrest warrant at the request of judicial authorities in the Netherlands, the statement said. 
  
 Authorities have not released his name, and a photo police issued showing his detention blurred his face. 
  
 The arrest comes a month after Internet users around the globe faced slowed-down service during the prolonged denial-of-service assault on The Spamhaus Project , a European spam-fighting group. 
  
 Security experts said the attack used more sophisticated techniques than most distributed denial of service, or DDoS, attacks and targeted the Web's infrastructure, which led to other sites performing slowly. 
  
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 In a DDoS attack, computers flood a website with requests, overwhelming its servers and causing it to crash or become inaccessible for many users. 
  
 Last month's attack appears to be part of a fierce feud between organizations that monitor spam and try to block it and companies that accuse spam blockers of unjustly blacklisting them. 
  
 The Spamhaus Project is a nonprofit that patrols the Internet for spammers and publishes a list of Web servers those spammers use. 
  
 Matthew Prince, CEO of Internet security firm CloudFlare, estimates the group may be responsible for up to 80% of all spam that gets blocked. 
  
 And last month, the group added a new name to its blacklist, CyberBunker, and said spammers use the company as a host to spray junk mail across the Web. 
  
 During his arrest, the suspect told authorities he was a diplomat and "minister of telecommunications and foreign relations of the Republic of CyberBunker," police said Sunday. 
  
 Last month CyberBunker -- a Dutch company housed in a former NATO nuclear bunker -- did not take credit for the attack against Spamhaus but didn't shy away from talking about it. 
  
 "This here is the Internet community puking out Spamhaus," Sven Olaf Kamphuis of CyberBunker told CNN in March. "We've had it with the guys. ... What we see right here is the Internet puking out a cancer." 
  
 Kamphuis and other critics say that Spamhaus oversteps its bounds and has essentially destroyed innocent websites in its spam-fighting efforts. 
  
 "Spamhaus itself is a more urgent danger" than spam, Kamphuis told CNN. "Pointing at websites and saying they want it shut down and then they get it shut down without any court order. That is a significantly larger threat to internet and freedom of speech and net neutrality than anything else." 
  
 In a statement Friday, Spamhaus thanked Dutch authorities for last week's arrest. 
  
 "Spamhaus will resolutely continue its mission to provide reliable protection against cyberthreats such as spam, malware and botnets and work with Internet service providers and organizations worldwide to create a safer Internet," the organization said in a statement. |||||

Write a summary.
– Spain has busted the man it says is behind the worst cyberattack ever, and CNN reports that the Interior Ministry says he apparently carried it all out from a van he used "as a mobile computing office, equipped with various antennas to scan frequencies." The 35-year-old Dutch national, reportedly named Sven Kamphuis, was arrested on Thursday in the city of Granollers, and stands accused in the massive Spamhaus slowdown. The AP adds that he also operated out of a bunker, "from where he even did interviews with different international media." He dubbed himself a diplomat from the "Telecommunications and Foreign Affairs Ministry of the Republic of Cyberbunker."