Doubts Emerge Over 'Leaked IS Documents' Identifying Thousands of Militants

German authorities are investigating tens of thousands of documents claimed to detail the identities and personal information of a large number of Islamic State (IS) militants, but doubts as to their authenticity are now also being raised.

The documents, which are said to include 23 question enrolment forms the group required from new recruits and date back to 2013, were obtained by British and German media outlets. Information included contact details, family members, and special skills.

If verified, other details, including countries the passed through en route to Syria or Iraq, special skills, and the name of the person who recommended them to IS, will prove invaluable to intelligence organizations. British broadcaster Sky News said some of the phone numbers listed were still active and believed to be in use by the group's members.

German media reported on the documents earlier this week, and the country's interior ministry confirmed on Thursday that they believed they were authentic. Interior Minister Thomas de Maizière told reporters that they would help with investigating and sentencing jihadists returning from Syria and Iraq.

At least 51 different nationalities were represented, including Americans, Canadian, British, French, and Germans, Sky News said.

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Syrian opposition media outlet Zaman Al Wasl, which also had access to the documents, said it had identified 1,736 jihadists from over 40 countries. It said 72 percent of those were Arabs, with the main nationalities being Saudi, Tunisian, Moroccan, and Egyptian. Turks reportedly made up the largest component of the remaining 28 percent, followed by French fighters. Zaman Al Wasl also said it had identified 122 recruits who opted to be suicide bombers.

Some of the names included in the trove of files were already well known, such as failed British rapper Abdel-Majed Abdel Bary, as well as his countrymen cyber-expert Junaid Hussain and Reyaad Khan, who appeared in a slick propaganda video. Hussain and Khan have since been killed in US-led airstrikes.

However, the documents also contain details of militants previously unknown to authorities who are now in the US, Canada, and northern Europe, as well as the Middle East and North Africa, according to Sky News. Many of these men, it said, had made multiple journeys through countries with high levels of extremist activity, including Yemen, Libya, and Afghanistan before travelling to Syria to fight and returning home again.

German authorities did not mention how it had obtained the documents, but Sky News said they had been provided by an IS defector who stole a memory stick containing them from IS's internal security chief. It added said the man, who went by the pseudonym Abu Hamed, was a former Free Syrian Army member and handed over the stick at an undisclosed location in Turkey.

However a number of experts have now called into question the authenticity of at least some of the documents due to a number of inconsistencies. These include different ways of writing IS's former name, "the Islamic State in Iraq and Syria," in Arabic, one of which did not correspond to previous usage, an unseen logo, and grammatical errors that Georgia State University researcher Charlie Winter told AFP were "big alarm bells."

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Sky News said Abu Hamed claimed to have defected because members of the Baath party of executed Iraqi despot Saddam Hussein's had taken over IS, leading to the collapse of Islamic law within the group. He also reportedly said it would give up Raqqa, the capital of its self-proclaimed caliphate, and move into desert areas of Syria and then to Iraq, where the group first formed as al Qaeda in Iraq.

The news channel also quoted Abu Hamed as claiming IS, the Syrian regime, and Kurdish militant group the YPG were working together to crush moderate Syrian rebel groups. There have been repeated accusations of collaboration between IS and the Syrian government, and the YPG have appeared to maintain tactical agreements with the regime. But the YPG have fought fiercely against IS and are seen by the US as a valued partner against the group.

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