An Israeli hacker said Tuesday he retaliated for a hack on Israeli databases that released the credit card information of thousands of Israelis last week, revealing what he said were hundreds of Saudi credit card numbers.

A week ago, Saudi hacking group Group-XP claimed it had obtained personal information of about 400,000 Israelis. Files containing the information were posted online by a hacker identifying himself as "0xOmar."

Checks carried out by the credit card issuers and the Bank of Israel, however, determined that the details of between 14,000 and 15,000 active cards had been exposed.

A further file was published on Friday by another hacker, identifying himself as "X,"and also claiming to be from "Group-XP." Bank Leumi warned people against downloading the new file, which it said may contain spyware.

In what is claimed to be an Israeli retaliation to that hack, an Israeli hacker named Omer Cohen and nicknamed "0xOmer," claimed to expose a considerable number of Saudi credit cards, along with personal information such as email addresses.

According to the list "OxOmer" released, over 200 Saudi credit card numbers and emails were exposed as well as the details of the citizens of other countries.

In an email to Haaretz, the Israeli hacker claimed to be in possession of the personal information of over 50,000 Arab citizens, including the credit card numbers originating from several Gulf states as well as Iran.

He identified himself as a 17-year-old Israel, who immigrated to Israel from the Ukrain at the age of 4 and has been interested in computers from an early age.

When asked whether he felt his move could hurt innocent people, the hacker said that he had chosen to expose personal information but not the card verification value (CVV) as to prevent internet users from making purchases.

The Israeli hacker also spoke of his decision to hack the accounts of Saudi royalty, writing that the action was "to signal to the Arabian regimes (of enemy states, mind you) that they must act against the criminals that are orchestrating these attacks from their territory."

"If they won't, and the attacks will continue, I'll hack into the king's accounts and maybe Saudi and Arab government websites," he said, adding that all of his operations were "just a warning."

"If the state won't deter against criminals and terrorists in cyberspace, we the citizens will," he added.

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