salafiTEHRAN (Fars News Agency – FNA) – The European Intelligence Service (EIS) decided in a recent meeting not to allow the Salafi fighters who have flown to Syria to join the terrorist groups to return to Europe again.

“The EIS studied the issue of Salafi fighters who enjoy European nationalities in its recent meeting on July 24 and decided that it should prevent the return of thousands of Salafi fighters to their countries in Europe,” an informed source told FNA on Wednesday on the condition of anonymity due to the secrecy of the issue.

According to the source, the European security officers have welcomed the exit of Salafi fighters from Europe, underlining that their stay in Syria will increase security in European territories.

“They have also decided to identify the origins of these fighters and the roots of their beliefs in Europe in a bid to prevent the training of a new generation of Salafi fighters on the continent,” the source added.

Earlier this year, the EU’s anti-terror chief said that hundreds of Europeans are now fighting with rebel forces in Syria against Bashar al-Assad’s government.

Gilles de Kerchove estimated the number in Syria at about 500.

Intelligence agencies are concerned some could join groups linked to al-Qaeda and later return to Europe to launch terrorist attacks.

The UK, Ireland and France are among the EU countries estimated to have the highest numbers of fighters in Syria.

“Not all of them are radical when they leave, but most likely many of them will be radicalized there, will be trained,” Mr. de Kerchove said.

“And as we’ve seen this might lead to a serious threat when they get back. ”

Across Europe, intelligence agencies have stepped up investigations, says the BBC’s Europe correspondent Duncan Crawford.

In Britain and Belgium they have increased efforts to track how people are recruited.

In the Netherlands, officials have raised the terror threat level there to “substantial” – partly over concerns about radicalized citizens returning from Syria.

Syria has been experiencing unrest since March 2011 with organized attacks by well-armed gangs against the Syrian police, border guards, statesmen, army and the civilians being reported across the country.

Thousands of people have been killed since terrorist and armed groups turned protest rallies into armed clashes.

The government blames outlaws, saboteurs, and armed terrorist groups for the deaths, stressing that the unrest is being orchestrated from abroad.

In October 2011, calm was almost restored in most parts of the Arab state after President Assad started a reform initiative in the country, but Israel, the US and its Arab allies brought the country into chaos through every possible means. Tel Aviv, Washington and some Arab capitals have been staging various plots in the hope of increasing unrests in Syria.