Names, addresses and phone numbers of some 22,000 ISIS recruits — and information about the network that recruited them — are reportedly part of a trove of data that Sky News says it received from a former member of the extremist group.

The identities of people from more than 50 countries, including Britain, European nations, the U.S. and Canada, are purportedly in the data, which Sky says it has shared with government authorities.

"Some of the telephone numbers on the list are still active," Sky reports, "and it is believed that although many will be family members, a significant number are used by the jihadis themselves."

It's not yet clear how many of the thousands of people named in the documents might have traveled to join ISIS, and how many may still be in their home countries.

Among the most intriguing elements said to be in the data trove: 23-line recruitment forms filled out by sponsors that begin with recruits' "name" and "fighter name" and then include their mother's maiden name and their blood type. Education and job experience are also covered; so are combat experience and "date and place of death" — implying that the paperwork was meant to follow the recruit once they'd joined ISIS.

The forms also reportedly include the question, "Who recommended him?" — which may help the authorities establish a crucial link between the terrorist organization and far-flung recruiters.

Some of the recruits listed in the files are Westerners who are known to have traveled to join ISIS, Sky reports, citing several cases of high-profile British recruits who have either been killed or whose whereabouts are unknown.

When Britain's Home Secretary Theresa May was asked about the leaked documents today, she replied, "I don't comment on specific national security matters, but I have seen the reports. Daesh poses a severe threat. The threat level in the UK is at severe and we have seen the attacks that have been perpetrated on mainland Europe over the last year."

May then added that she's urging Britain's allies to share information and to restrict the movement of firearms within Europe.

The news comes days after German media outlets reported having obtained a similar set of documents. According to Deutsche Welle, a representative of Germany's federal police says they have the documents and that they're authentic. It's unclear whether the sets of data are the same.

NPR's Soraya Sarhaddi Nelson reports from Berlin that Germany's Interior Ministry "says the files could also undermine the ability of ISIS to recruit and inspire new fighters."

"It's not known how many ISIS fighters are in Syria and Iraq, but estimates range between 30,000 and 100,000," Soraya adds.

Sky News said it obtained the data via a memory stick provided by a former member of the Free Syrian Army using the name Abu Hamed, who joined ISIS but then quit because he believes the group stopped following Islamic law and is too heavily influenced by former members of Iraq's Baath party.

"It's far from Islam," the man tells Sky News' Stuart Ramsay, during an interview in Turkey in which he wore a scarf to obscure his face.

When asked whether the information might be used to destroy ISIS, the man answers, "God willing, if we give it to those who will use it, of course."

Once the administrative forms were filled out, Ramsay reports, they were given to ISIS' head of internal security, who then put the data on the memory stick.

Ramsay also says his contact told him that ISIS is in the process of moving its headquarters from Raqqa, Syria, to the desert and then to Iraq. He also claimed that in Syria, ISIS has collaborated with President Bashar Assad's government and other groups to fight the country's moderate opposition forces.

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