GAZIANTEP, Turkey (AP) — Along the border near the southern Turkish city of Gaziantep, a wall of giant concrete blocks is going up as Turkey tries to seal off a region that for years was a jihadi highway through which thousands of extremist fighters flowed to join the Islamic State group in neighboring Syria.
Turkey has always denied permitting the movement of IS militants into Syria and insists it has been doing its best to stop the transit, even before construction on the massive wall began late last year.
Documents obtained by The Associated Press, however, tell a different story, showing a pattern of porousness along Turkey's 566-mile- (911-kilometer-) long border with Syria that has been vital for the extremist group's expansion as it built its self-declared "caliphate."
The AP analyzed 4,037 "entry documents" logged by the Islamic State group for its fighters entering from Turkey into Syria between September 2013 and December 2014. Around three-quarters of them entered through three particular crossing areas.
Those fighters alone would make up between 25 to 40 percent of the estimated total of IS's foreign recruits, and they likely do not represent all fighters that entered through Turkey during that period. According to CIA estimates, IS had 20,000-31,500 fighters by the end of 2014, around half of them foreigners. The documents were leaked to a Syrian opposition news site, Zaman al-Wasl, which provided them to the AP.
A deadly bombing of Istanbul's international airport on June 28 that killed 44 people raised fears that Turkey is paying a price for IS's free movement through its territory. Some analysts believe IS struck in revenge for Turkey's support for the U.S-led coalition against IS, its tighter border controls and its backing for rebels working to recapture the last stretch of the border that the extremist group still holds on the Syrian side.
The ease with which militants crossed into Syria from Turkey has long brought accusations that Ankara's determination to oust Syrian President Bashar Assad by backing Syrian rebels trumped any concerns over fueling the jihadi movement. The relatively open border was crucial for rebels, including ones backed by the United States, and the fighters used Turkish territory as a crucial rear base and supply route. It was also a life-saving escape route for some 2.75 million refugees who fled into Turkey and an avenue for humanitarian aid to opposition-held areas of Syria.
"Until the rise of ISIS in 2014, Turkey was basically turning a blind eye to radical foreign fighters who were crossing into Syria," said Turkish analyst Soner Cagaptay, an expert at the Washington Institute for Near East Policy, referring to the group by its former acronym. "Not because Turkey was in favor of radicals or supported radicals ... but because they thought they were war-hardened fighters who could accelerate the demise of the Assad regime, helping Turkey toward its final objective."
A Turkish official, who spoke on condition of anonymity in line with government protocol, rejected the claim Ankara ever knowingly allowed jihadi fighters to cross into Syria. He pointed out that Turkey arrested thousands of foreign fighters and sent them back to their home countries.
He argued that source countries that allowed such dangerous elements to head to Turkey should be the ones under scrutiny. He said Ankara's requests to other governments, including in the European Union, for intelligence sharing about these suspects were not taken seriously until late 2014.