Foreign Ministry tells countries their citizens face arrest if they arrive in Israel • Authorities expect between 500 and 1,000 activists on Sunday • Israel Law Center asks attorney-general to prosecute pro- Palestinian activists participating in protest.

Israeli security forces, both domestically and abroad, are taking preemptive measures to prevent pro-Palestinian activists, mainly from Europe, from boarding flights to Israel as part of the scheduled "flightilla" protest starting Sunday.

The planned protest aims to flood Israel´s Ben-Gurion International Airport with demonstrators on Sunday, who will then travel to other locations to take part in demonstrations against Israeli policy in the Palestinian territories.

Foreign Ministry representatives have contacted several countries requesting that they call on their citizens not to participate in the fly-in, and to further warn them that if they choose to board the flights anyway, they will face arrest upon their arrival in Israel.

In addition, Israel has warned European airlines that if they allow activists to board their planes, the airlines will be responsible for covering the costs of deportation back to their home countries. Security officials have sent lists of names of potential activists to the foreign airlines in an attempt to thwart their arrival.

The Israel Law Center, a civil rights organization, has asked the attorney-general to prosecute pro-Palestinian activists arriving in Israel as part of the "flightilla" rather than simply deporting them, as the security authorities intend to do, Israel Radio reported on Thursday.

The organization claims that releasing the activists without bringing them to justice is not reasonable and is likely to be harmful as the activists will continue to try to enter Israel.

The Foreign Ministry said this week that a number of countries have agreed to issue warnings against participating in the "flightilla." Foreign Ministry spokesman Yigal Palmor said that the ministry was coordinating its steps with several foreign consulates ahead of the scheduled fly-in.

The Population and Immigration Authority on Wednesday issued a list of activists who have been denied entry into the country, together with a letter asking foreign airlines to prevent the activists from boarding flights heading to Israel. Authorities estimate that between 500 and 1,000 anti-Israel activities will try to enter the country on Sunday, and will attempt to go to areas under Palestinian Authority rule. According to "flightilla" organizers, about 1,500 activists will try to make their way to Israel.

The Israel Police was also gearing up for the possible arrival of the activists, and began to station forces at the airport on Thursday. Overall, the police was set to deploy more than 650 officers ahead of the fly-in.

However, police sources said they expected not much more than a publicity stunt, adding that if the activists were to disrupt the peace or stage riots it would be fairly easy to contain them.

"The challenge is not the riots, even if there are hundreds of activists. This is not the Temple Mount, nor is it Silwan or the Northern District. What we want is to prevent the organizers of the fly-in from making any public relations achievements like those that were achieved in the Mavi Marmara incident," a senior police officer said on Wednesday, referring to the May 2010 deaths of nine Turkish activists headed for Gaza on a protest ship.

As part the lessons learned from previous fly-ins, a large number of policemen who will be stationed at the airport will be dressed in civilian clothing, so as not to draw any attention to the activists.

The police will also try to minimize media coverage of the fly-in in efforts to eliminate the incentive for a provocation. Security authorities believe the peak arrival of the activists at the airport will be at around 9 a.m. on Sunday with the first ones arriving from Turkey. The airport demonstration is expected to last until about 7 p.m. with activists set to travel on a long list of flights from across Europe. Authorities say there is also a possibility that individual activists will arrive at the airport after the end of the Passover holiday on Saturday.

Police intend to divert activists arriving on Sunday to Terminal 1, which will be completely evacuated, and not the busier Terminal 3. Police forces are also preparing for the arrival of right-wing activists, who plan to hold counter-protests at the airport.

Although police preparations have already been finalized, some officers this week expressed criticism of too much "unnecessary chatter" taking place in the police. The officers claimed that some confidential details of the fly-in preparations have been exposed, and that this was playing into the hands of the organizers.

Apparently, police preparations were initially made behind closed doors with the intent of keeping the media away.

But statements made by Public Security Minister Yitzhak Aharonovitch and senior police officers made the details of the preparations impossible to keep under wraps.

"The decision was to keep a lid on the details so that this information would not get to the anarchists who are planning to come to Israel," a senior police officer said, adding that it would have been better had Aharonovitch not been interviewed on the subject.

Another senior officer said that, "the revelation of the preparations and all the publicity surrounding the activists is turning the fly-in into a battle between David and Goliath and that´s exactly what the organizers of the ´flightilla´ want in order to embarrass us in front of the entire world."

The Public Security Ministry issued a statement saying, "the media already had all of the information in great detail, and most of the reports have come from the anarchists anyway."

The left-wing activists coming are reportedly planning to stay at the Palestinian Bethlehem Peace Center. The left-wing movement Gush Shalom on Wednesday called on the police to cancel their preparations ahead of the arrival of the activists.

Meanwhile, two Palestinians and two foreign radical left-wing activists were arrested on Wednesday in Hebron after they attacked Israeli security forces.