A German court on Monday passed a ruling that police in Germany cannot remotely search criminal suspects' computer hard drives over the Internet without their knowledge.

The decision of the Federal Court of Justice in Karlsruhe bars police from using the online "Trojan Horse" method, which involves using a computer program to remotely search through hard drives over an Internet connection, unless parliament passes a law explicitly allowing it.

Arguing that stealth searches were indispensable to investigating criminals and especially terrorists, Interior Minister Wolfgang Schäuble, the country's top security official responsible for police, called for the government to go ahead and seek swift changes in the law.

The decision came in response to a request made by the Federal Prosecutor's Office, which had sought to use Trojan Horse methods to investigate the suspected terrorist group by hacking into their network.