Germany has recovered personal data files belonging to ISIS.The files have details of hundreds of recruits and is believed to be genuine.

Britain’s Sky News reported to have found 22,000 ISIS files on the border with Turkey and Syria. A former fighter believed to have stolen the information from the head of Islamic State’s internal security police.The files reveal ISIS fighters’s name, the place they come from, phone number and names of sponsors and recruiters.

The documents included 23-question forms, filled out by recruits. The data revealed nationals from 51 countries.

The files give an insight of past and present fighters and their operations across the Mideast. The information is yet to be determined whether they are authentic.

U.S. army Col. Steve Warren, spokesman for the US-led coalition against ISIS, said the file could be very useful in the fight against the group.

“This would allow the law enforcement apparatus across the world to become much more engaged and begin to help do what we can to stem this flow of foreign fighters — so we’re hopeful that its accurate and if so we certainly plan to do everything we can to help,” said Warren.

Germany’s Sueddeutsche Zeitung newspaper reported similar files. It said that anti-ISIS Kurdish fighters had ISIS data and videos, reports CBC News.

Markus Koths, a spokesman for Germany’s Federal Criminal Police Office denied to disclose how the information was obtained due to “tactical reasons.”

“We believe there is a high probability that these documents are genuine.These documents are of significance for us for prosecutorial reasons and for threat prevention,” said Koths.

A Qatari-based Syrian website, Zaman Al-Wasl, published a similar data. It referred to two Germans(Kerim Marc B and Abdelkarim B), who are currently on trial in Germany. And revealed two other Germans (Farid Saal and Yassin Oussaiffi) who appeared in the ISIS videos, according to a BBC report.

The documents also cited names of fighters who entered different areas under ISIL in 2013. However, it is still unclear whether the new data will reveal the group’s current membership. There is no approximate data on how many ISIS militants are there in Iraq and Syria. Roughly it ranges between 30,000 and 100,000.