Spanish and Moroccan police have arrested four Moroccan men suspected of links to militant Islamist activity, the Spanish Interior Ministry said on Wednesday.



The arrests followed two years of police investigations and stemmed from monitoring two people who had lived in Spain but had gone to join Islamic State in Syria and Iraq, the ministry said in a statement.



These two formed a recruiting cell and then established off-shoots in Spain and Morocco, each containing a further two members.



The two men arrested in Spain were charged with enlisting and indoctrinating recruits to fight in Syria and Iraq with the use of social media. They had direct contact with Islamic State through the Syrian unit, the ministry said.



The two others were arrested in Morocco.



Spain has been on high alert and has stepped up security measures following Islamist militant attacks in Paris last year. Spain has arrested around 40 people suspected of links with Islamist militants this year so far.