Israel has begun inspecting emails of some Arab visitors and expelling those visitors who are deemed a threat to the country.

Israeli airport security officials are asking these visitors to log on to their email accounts so officials may conduct a security search for any incriminating activities. The inspections have targeted Arab visitors in an effort to root out any individuals with histories of pro-Palestinian activism.

At least three Arab-American women have been expelled in recent weeks after their email accounts were searched.

Israel has become increasingly strict following a series of run-ins with international activists in recent years, highlighted by a deadly clash in May 2010 between Israeli naval commandos and a flotilla trying to break Israel’s naval blockade of the Gaza Strip. Both sides accused the other of provoking the violence in which nine Turkish activists were killed.

Since then, Israel has prevented international activists from arriving on similar flotillas as well as a pair of “fly-ins” by pro-Palestinian activists. Israeli officials acknowledge they used social media accounts, such as Facebook and Twitter, to identify activists ahead of time and prevent them from boarding flights to Israel.

Emanuel Gross, a law professor at Haifa University, said such a practice would seem to be illegal in Israel.

“In Israel, you need a search warrant to go into somebody’s computer,” he said. “I’m skeptical that the security guards asked a judge first for a warrant, and I’m skeptical that a judge would give it.” — jta & ap