Following the 1949 Armistice Agreements, which ended the 1948 Arab–Israeli War, many Palestinian Arabs began attempting to cross the Green Line and return to their homes in the recently established State of Israel. Most of these crossings took place from the Jordanian-annexed West Bank and the Egyptian-occupied Gaza Strip, and were largely motivated by dismay among Palestinians who had fled or been expelled from Israeli territory. Although the majority of Palestinian crossers sought to return unarmed to retrieve their belongings or possibly settle among Arab communities in Israel, this period also witnessed the Palestinian Fedayeen insurgency, which was met with Israeli reprisal operations. Approximately 2,700 to 5,000 Palestinians were killed by Israeli troops until the 1956 Arab–Israeli War, when the frequency of these crossings died down significantly. During the 1967 Arab–Israeli War, Israel captured the West Bank from Jordan and the Gaza Strip from Egypt. A period of mass employment inside of the Israeli-occupied territories was then facilitated by the regular entry of Palestinians into Israel. Nevertheless, the incentive for both sides—higher wages for Palestinian workers in Israel and the growing reliance of the Israeli economy on them—kept conditions relatively stable until the First Intifada (1987–1993), when Palestinian attacks against Israelis prompted Israel to increasingly restrict Palestinian entry into the country. For the next decade, however, as many as 140,000 Palestinians from the occupied territories successfully obtained legal residency in Israel by right of spousal unification, which could be claimed by an Israeli citizen upon marriage to a non-citizen. The Second Intifada (2000–2005) drastically intensified Israel's policy of separating Israel proper from the occupied territories. In 2003, the Citizenship and Entry into Israel Law made Israeli citizens ineligible to apply for a permit for their Palestinian spouse to immigrate to Israel from the occupied territories. Most notably, while the Gaza Strip barrier had already existed since the 1970s, Israel also constructed the West Bank barrier, which is monitored by built-in military checkpoints and watchtowers to prevent unauthorized Palestinian crossings into Israeli territory. Work permits issued by Israel to Palestinians living under the Palestinian National Authority have generally decreased and are often cancelled entirely during phases of surging violence in the Israeli–Palestinian conflict.