RABAT – Clashes between security forces and protesters in Western Sahara killed several people on Monday after Moroccan authorities stormed the site of the disputed territory's biggest anti-government protest in decades. Morocco said two of its police officers and a firefighter were killed by protesters, while the pro-independence Polisario Front said Moroccan security forces killed a 26-year-old activist during a raid on a protest camp in the desert. The violence was some of the worst in years in Western Sahara, a former Spanish colony annexed by Morocco in 1975 and which ever since has been the subject of a bitter dispute between Rabat and independence campaigners. Clashes erupted on the day officials from Morocco and the Polisario were gathering near New York for talks brokered by the United Nations and aimed at breaking the stalemate in their dispute, Africa's longest-running territorial conflict. "It is highly unfortunate that this operation and the events preceding and following it have affected the atmosphere in which these talks are being held," UN spokesman Martin Nesirky told reporters. "We call on all parties involved to exercise the utmost restraint in the hours and days to come." The day of clashes began before dawn when Moroccan security forces broke up a protest camp of thousands of tents near Western Sahara's main city of Laayoune. For a month, the camp had been testing Morocco's tolerance of dissent. Soon after, several hundred of the people forced out of the camp took their protest to the streets of Laayoune, where they blocked roads with burning tires, set fire to cars, and threw stones at police. One protester told Reuters from the scene: "Anger is boiling over. We are in the streets protesting against Morocco." Western Sahara is a sparsely populated tract of desert about the size of Britain, with rich fishing grounds off its coast and reserves of phosphates, used to make fertilizer and detergent. Morocco says the territory should come under its sovereignty, while the exiled Polisario Front says Western Sahara is an independent state. The Polisario waged a guerrilla war against Moroccan forces until the United Nations brokered a ceasefire in 1991. Since then, several rounds of talks have failed to produce a deal. Moroccan authorities on Monday traded accusations of violence and brutality with the exiled Polisario, which is based in desert camps in neighboring Algeria. A Moroccan security official, who did not want to be identified, told Reuters that a paramilitary policeman and firefighter were stabbed to death by protesters during the operation to dismantle the protest camp. The same official later said a policeman was stabbed to death by demonstrators in a main street in Laayoune during a protest there. In a statement released in Algeria, the Polisario said protester Babi Mahmoud El Guerguar was killed by the Moroccan army in what it called a "barbarous act." The Moroccan security official denied any protester was killed. For the past month, thousands of protesters had been living in the tent camp demanding jobs and better living conditions - while avoiding references to Western Sahara's political status.