COPENHAGEN, Denmark (AP) -- A new wave of Europeans is heading to Syria, their ranks soaring in the past six months as tales of easy living and glorious martyrdom draw them to the rebellion against Bashar Assad.
The western Europe-based rebels, mostly young men, are being recruited by new networks that arrange travel and comfortable lodging in the heart of rebel territory, and foster a militant form of Islam that Western security officials fear will add to the terror threat when the fighters return home.
The 11 western European countries with the biggest contingents in Syria are estimated to have some 1,200-1,700 people among rebel forces, according to government and analyst figures compiled by The Associated Press. That compares to estimates of 600-800 from those countries in late spring.
The surge has occurred particularly in France, Germany, Belgium and Sweden. It reflects the increasing ease of travel to Syria's front lines and enthusiastic sales pitches by the first wave of European volunteers.
A 21-year-old Dane became interested in Syria during a prison term in Denmark for assault and robbery, mainly through online rebel videos. He made two trips into Syria that totaled a little more than one month. He drove trucks carrying relief supplies and transported people, he said, but never fought. Nevertheless, he posted photographs online of himself with heavy weapons.
"It is my duty to travel down there. This is a Muslim cause," said the young man, a Muslim convert who did not want to be identified for fear of pursuit by authorities.
On his third trip this year, he said, he was stopped at passport control in Istanbul and sent back to Denmark. No reason was given, but he believes his time with the opposition put him on the intelligence community's radar. He described being questioned multiple times by Danish intelligence agents, including at the Copenhagen airport after returning from Syria for the first time.
"Right now, I cannot go to Syria," he said. "I wanted to help with humanitarian work and fight."
Recruitment drives targeting people like the Dane are growing in intensity. The Islamic State of Iraq and the Levant, one of two main al-Qaida linked groups fighting in Syria, is producing a video featuring a battalion of British fighters "who will be talking to other British Muslims to try and motivate, inspire and recruit them," said Shiraz Maher, a researcher at the London-based International Center for the Study of Radicalization. In France, authorities in recent weeks say they have dismantled two networks of former fighters who have returned from Syria to recruit.
Governments have reported no examples of ex-fighters from Syria creating trouble on their return. But France remains haunted by the case of Mohammed Merah, a French youth of Algerian descent who trained in Pakistan and returned to southern France to attack a Jewish school and kill seven people in 2012. The French government has since outlawed training in terrorism camps abroad.
The United States has also sounded the alarm about young Americans headed to Syria. But distance and expense have kept the numbers from the U.S. far lower: about 20 American citizens, according to the ICSR.
For the Syrian rebels, attracting fresh bodies for the fight has become a matter of urgency as Assad makes gains in the civil war with the help of Iran and Shiite militant group Hezbollah.
And despite their lack of battlefield experience, Europeans are also a powerful propaganda tool for a rebel force that is trying to show that its appeal goes wider and deeper than the Middle East. The Europeans have the added potential of being able to raise money in places far wealthier than Iraq, Afghanistan and Chechnya, where many of the other foreign rebels have their roots and fighting background.
Many, if not most, are from second-generation immigrant families from outside Europe with parents who describe themselves as secular and fully integrated. Others -- like the Dane -- are converts with no prior ties to Islam.
France has counted between 300 and 400 European rebel fighters in Syria; Germany has counted more than 220; Belgium puts its number at 150-200, according to the International Center for the Study of Radicalization, citing recent figures that double previous estimates. Sweden is about to double its estimates to 150-200, according Magnus Ranstorp, a terrorism specialist with the Swedish National Defense College. Britain's total has stayed stable at less than 150, according to recent estimates from U.K. security officials. The Netherlands estimate, which officials said is rising rapidly, is 100-200, according to government and analyst figures. Denmark's intelligence service estimates "at least 80" fighters from there -- with similar numbers from Spain, Austria and Italy. Norway believes about 40 of its citizens have left for Syria in the past year.