Turkish hackers have posted two large files that could expose the personal data of more than 100,000 Israeli citizens, according to news reports.

Israeli observers fear that the data thefts could be a concerted effort by Turkish hackers to target Israeli nationals, according to the reports. The two countries have been in conflict since Israeli forces intercepted a Gaza-bound aid flotilla on May 31. Nine pro-Palestinian Turkish activists were killed in the confrontation.

During the weekend, Israeli blogger Erez Wolf said in his blog on We-CMS that he had found an Excel spreadsheet with more than 32,000 e-mail addresses and passwords published on a Turkish forum. The items were obtained through numerous hackings since the Gaza flotilla incident in late May, he said, including Israeli accounts on Facebook, Gmail, and Messenger.

On Sunday, TheMarker.com website reported another file is circulating on the Internet that contains the email addresses of an additional 70,000 Israeli Web users.

One of the sources of the data, Israel's Pizza Hut, confirmed it has been hacked. The company said Saturday that email addresses and passwords of 26,476 customers who ordered pizza from the company's website in early June had been stolen. Pizza Hut officials said credit card data is not stored on the website.

The Israeli classified ad site called Homeless also conceded that its site has been hacked. No personal details were disclosed in the hack, according to the site, although "partial" user data may have been revealed.

"The hacking succeeded, and the hackers used the information in their possession to enter accounts on other websites," Wolf says. "Assuming that many surfers use the same email, same password, and same user name to register on all the sites that require registration (as it's easier to remember), the email and password from the hacked site will be the same e-mail and password that will get them into Gmail, Facebook, Messenger, and more.

"When I say more, I also mean PayPal. From what I've been able to learn on the forum, the hackers penetrated PayPal accounts of Israelis, and their bank accounts, and also obtained credit card details."

The sites did not reveal how they were hacked.

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