is also a small merchant population, who sell goods to travellers. Major Sahrawi political events, such as Polisario congresses and opening sessions of the Sahrawi National Council (the SADR parliament in exile) are held in the zone (especially in Tifariti and Bir Lehlou), since it is considered socially, politically and symbolically important to conduct political affairs on Sahrawi land. Polisario Force strength The Polisario troops (of the Sahrawi People's Liberation Army (SPLA) in the area are divided into seven "military regions", each controlled by a top commander reporting to the President of the Polisario proclaimed Sahrawi Arab Democratic Republic. The total size of the Polisario's guerrilla army present in this area is unknown. Some sources claim between 3,000 and 6,000 men, while others rise the number up to 12,000, with additional combatants stationed in Algeria, Mauritania or having been demobilized due to the cease-fire. These forces are dug into permanent positions, such as gun emplacements, defensive trenches and underground military bases, as well as conducting mobile patrols of the territory. Incidents in the area A concentration of forces for the commemoration of the Saharawi Republic's 30th anniversary were however subject to reproach by the United Nations, as it was considered an example of a cease-fire violation to bring such a large force concentration into the area. Minurso reports that there are on average 2–4 such violations in the whole Western Sahara territory each month, between the two sides. In addition to this, there are several more violations related to local commanders on both sides refusing the inspection of their forces by Minurso personnel. As an example, the mission homepage quotes the month of June 2006, when there were "189 such FMO [freedom of movement]-violations, all related to the denial of UNMO [UN military officers] entry into the parties' strong-points and units." Annual demonstrations against the Moroccan Wall are staged in the region by Sahrawis and international activists from Spain, Italy and other mainly European countries. These actions are closely monitored by the UN. See also History of Western Sahara List of cities in Western Sahara Safe Zone (Syria) United Nations Safe Areas Demilitarized zone References External links United Nations (Map) Minurso Deployment as of October 2006, Map No. 3691 Rev. 53 United Nations, October 2006 (Colour), Department of Peacekeeping Operations, Cartographic Section Sahrawi Arab Democratic Republic Geography of Western Sahara Polisario Front Western Sahara conflict 1991 establishments in Western Sahara