The five were detained on accusations of praising terrorism after they allegedly put on the Internet speeches by Osama Bin Laden, explanations on how to make bombs and videos showing Islamic terrorists training and firing weapons and carrying out executions.
The ministry said in a statement today that the men had been under investigation since 2012, shared content from jihadist sources linked to al-Qaida and were radicalizing themselves.
Police raided three homes in Barcelona during the investigation. The men were not identified. Praising terrorism has been a crime in Spain since 1995, when it was introduced to counter the armed ETA Basque separatist movement.