Just a few weeks after German authorities opened a national Cyber Defense Center in Bonn it was attacked by hackers and now officials are struggling to arrest all of those involved.

While security authorities reported they had arrested two members of the hacking group linked to the attacks, the group Thursday released a statement saying that only its leader was under arrest. The 23-year-old leader of the so-called "n0n4m3 cr3w" (No Name Crew), calling himself Darkhammer, was arrested on Sunday, the Office of Criminal Investigation in the German state of Nordrhein-Westfalen reported this week.

The Federal Criminal Police office issued a press release on Tuesday saying that it had searched the apartment of a second suspect. Responding to that arrest and media reports regarding those taken into custody, the hacking group said in its statement: "Apparently none of the suspects is a member of the No Name Crew."

Members of the No Name Crew had claimed responsibility for infiltrating computers of the federal police and the customs service. They were able to steal information from servers running the spy program Patras and put it on their website. Patras is used by customs authorities, the federal police and police in the German states for tracking serious criminals. After the attacks were uncovered several federal and state authorities temporarily shut down their servers.

The attacks first became known already on July 8 but attracted bigger attention just after German newspaper "Bild am Sonntag" on Sunday cited a confidential report by the federal information security agency, BSI, saying that computers of the federal police had been infected by Trojans for months without detection.

The hacking group now offers an encrypted file for downloading on its website stating that it had collected e-mails and confidential data from the police and customs authorities. The group said it would release the password for the encrypted file should police arrest more of the group's members.

"The terrifying fact about these attacks is that the delinquents are quite young. If these 17-year-old schoolboys are able to do that, what would happen if a much more experienced hacker would attack?" said Lars Sobiraj, editor-in-chief at the German-speaking online magazine gulli who interviewed members of the group this week.

In the interview, members of the group said they regarded their hacking as a wake-up call for the German public to see that the state kept the population under permanent surveillance. The group announced on its website that it will initiate more attacks. "New targets have been chosen," it said.

The attacks came just four weeks after German Federal Secretary of the Interior Hans-Peter Friedrich opened the Cyber Defense Center. The center is run by the BSI, the federal office for the protection of the constitution and the disaster control agency. The authorities whose systems were attacked also contribute to the operation of the center.

A spokesman of the BSI that leads the center against cyberattacks said Thursday that the agency would not comment about the events due to the ongoing investigations.

The center against cyberattacks has been criticized for not having the ability to fight electronic attacks. After its opening in June, Memet Kilic, a member of the Green party that is part of the opposition, said the center did not have enough financial and human resources. According to the BSI, the center has 10 full-time employees.

In an interview with the news magazine "Der Spiegel" this week, Klaus Jansen, leader of the German union of police detectives, said that security authorities do not have enough experts working with them to effectively fighting cybercrime.