Six suspected supporters of the Islamic State (IS) were arrested in coordinated raids in Spain, Germany and the UK on Wednesday morning. The group allegedly ran a propaganda network and helped recruit potential fighters.

According to Spain's Interior Ministry, investigators arrested four suspects in the tourist town of Palma de Mallorca. One person was arrested in the UK and one in Germany. The ministry announced the arrests on Twitter.

In Dortmund, police arrested a 28-year-old Spaniard, who was being investigated for allegedly supporting the group. A judge will decide in the next weeks whether he will be extradited to Spain. State Criminal Police (LKA) in Germany's North Rhine-Westphalia were involved in the operation. 

In Birmingham, authorities arrested a 44-year-old man who was a Salafist imam well known to them. He allegedly led the group.

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Series of videos

The investigation began in 2015, according to the Interior Ministry, when the suspects were identified in a series of web videos that showed a Spanish man being indoctrinated and sent to Syria.

According to investigators, the six detainees were part of an IS cell. They had allegedly made videos in which they glorified jihad and supported suicide attacks in Europe.

Read: Madrid to Manchester: A chronology of terror in Europe

The group had held weekly clandestine meetings to indoctrinate more followers. It also operated on social media. 

The British imam had traveled to Mallorca to set the cell up and act as its spiritual leader, according to the Interior Ministry.

The detainee in Germany had made contact with the Salafist imam detained in the United Kingdom and maintained contact with the Mallorca group, the ministry reports. He allegedly took part in the videos.

The police forces cooperated using EU agencies set up to help share information related to fighting crime within member states: Europol, Eurojust and Sirene.

Spanish police have arrested 178 people accused of links to militant groups since raising the security alert to the country's second highest level in June 2015.

Last week police in Madrid arrested three Moroccan terror suspects, one of whom was classified as "extremely dangerous." The 32-year-old was allegedly planning an attack in the Spanish capital under the banner of IS.

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aw/rg (dpa, Reuters, AP, AFP)