Israel's internal intelligence service is warning Israelis to be careful when using Facebook, saying Arabs are trying to recruit spies through the social networking site.

The Shin Bet security agency is telling Israelis not to answer unsolicited messages or share telephone numbers and other sensitive information over the Internet.

It cites a number of recent incidents in which violent groups tried to recruit Israelis through Facebook and other sites. In one instance, it says a man who introduced himself as a Lebanese agent contacted an Israeli Facebook user and offered money for information about Israel.

The Shin Bet also cautions Israelis against agreeing to seemingly innocent meetings proposed online by people they don't know, saying the messages might be posted by militants looking to kidnap or kill.

Eight years ago, an Israeli teenager was killed after being lured to the West Bank by a young woman he met on the Internet. More recently, Hamas militants in the Gaza Strip have been using Google Earth for better precision when firing rockets at southern Israeli cities.

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