Boy scouts hold up the Palestinian flag and a black flag that reads "There is no solution but the right of return", as they commemorate the 1948 creation of the Jewish state known as the "Nakba." US President Barack Obama warned that political turmoil battering the Middle East made it "more vital than ever" that Israel and the Palestinians get back to the negotiating table. (AFP/Saif Dahlah)

Palestinian children hold their national flags while marching on the streets during rally marking the anniversary of the mass displacement of Palestinians surrounding Israel's establishment in 1948, at Nuseirat refugee camp, central Gaza Strip, Tuesday, May 17, 2011. The rally marked an annual day of commemoration for the Palestinian people of the displacement that accompanied the creation of Israel in 1948. (AP Photo/Adel Hana)

A Palestinian girl wears a headband with Arabic that reads ' Allud, We shall definitely return' during a rally at Nuseirat refugee camp, central Gaza Strip, Tuesday, May 17, 2011. The rally marked an annual day of commemoration for the Palestinian people of the displacement that accompanied the creation of Israel in 1948. (AP Photo/Adel Hana)

A Palestinian boy wears a headband with Arabic that reads 'Ager, We shall definitely return' next to a poster representative a 'Nakba,' Arabic for catastrophe, during a rally at Nuseirat refugee camp, central Gaza Strip, Tuesday, May 17, 2011. The rally marked an annual day of commemoration for the Palestinian people of the displacement that accompanied the creation of Israel in 1948. (AP Photo/Adel Hana)

Palestinian children look through the window during a rally at Nuseirat refugee camp, central Gaza Strip, Tuesday, May 17, 2011. The rally marked an annual day of commemoration for the Palestinian people of the displacement that accompanied the creation of Israel in 1948. (AP Photo/Adel Hana)

A Palestinian boy with his face painted with the Palestinian flag wears a headband with a key with Arabic that reads 'We shall return' during a rally at Nuseirat refugee camp, central Gaza Strip, Tuesday, May 17, 2011. The rally marked an annual day of commemoration for the Palestinian people of the displacement that accompanied the creation of Israel in 1948. (AP Photo/Adel Hana)

Palestinian youths hold up flags as they participate in a bicycle rally marking the anniversary of the mass displacement of Palestinians surrounding Israel's establishment in 1948, in the West Bank city of Jenin, Monday, May 16, 2011. Text on shirts reads in Arabic: 'We shall return, 1948'. (AP Photo/Mohammed Ballas).

A Palestinian man walks through the checkpoint in the West Bank town of Bethlehem on his way to Jerusalem, Tuesday, May 17, 2011 (AP Photo/Bernat Armangue)

Palestinian mourners carry the coffins of three Palestinians wrapped in the Palestinian flags who killed when Israeli soldiers opened fire on Sunday at protesters who approached the village of Majdal Shams at Syria's border with the Israeli-controlled Golan Heights, during a funeral procession at Yarmouk Palestinian refugee camp in Damascus, Syria, on Monday May 16 2011. Israeli troops clashed with Arab protesters along three hostile borders on Sunday, leaving people dead and dozens wounded in an unprecedented wave of violence marking the anniversary of the mass displacement of Palestinians surrounding Israel's establishment in 1948 (AP Photo/Bassem Tellawi)

Surrounded by media members, Hassan Hijazi, a Syrian man who infiltrated Israel when a large crowd breached the border on Sunday, attends a remand hearing in a Tel Aviv court, Israel, Tuesday, May 17, 2011. Hijazi, 28, spent a full day hitchhiking and rising a bus next to an Israeli soldier as he made his way some 130 miles (200 kilometers) from the Golan Heights to a Tel Aviv neighborhood to find the home he said his family lost during Israel's 1948 establishment, he said.(AP Photo/Ariel Schalit)