Riot police armed with batons clashed with protesters trying to hold a demonstration against the government's economic policies, and seven officers were injured, officials said Friday.
Television reports showed images of objects being thrown and officers armed with batons hitting protesters near the interior ministry in Madrid late Thursday.
A national police spokeswoman declined to say Friday how many protesters were hurt. But she said four demonstrators were detained for alleged public disorder, including Gorka Ramos, a reporter for online newspaper lainformacion.com. The spokesman spoke on condition of anonymity in keeping with police policy.
The news outlet said on its website that 13 protesters were treated for injuries and that Ramos was being held in a Madrid jail, unable to speak to his family or employer.
It published images of Ramos with blood stains on his nose and right eye being led away by police in riot gear. Ramos had been carrying appropriate identification and was covering the protests live through his Twitter web feed column, lainformacion.com said.
Citizens angry about the government's austerity program during Spain's economic crisis have been demonstrating for four days in Madrid, angry that police are preventing them from re-erecting a protest camp in the central Sol plaza where they had held protests since May.