Largest protest yet in Syrian city loyal to Assad (AP) BEIRUT - Syrian security forces fired tear gas and live ammunition to disperse thousands rallying Friday in Aleppo in what activists said was the largest protest yet in a city that has largely remained loyal to President Bashar Assad during the country's 15-month uprising. The protest pointed to rising anti-regime sentiment in Syria's largest city, particularly after a raid on dormitories at the city's main university killed four students and forced the temporary closure of the state-run school earlier this month. Complete Coverage of the Syrian Conflict The May 3 raid at Aleppo University was an unusually violent incident for the northern city, a major economic hub, where business ties and the presence of significant populations of sectarian minorities have kept residents largely on the side of the regime - or at least unwilling to join the opposition. On Thursday, some 15,000 students demonstrated outside the gates of Aleppo University in the presence of U.N. observers, before security forces broke up the protest. Even bigger numbers took to the streets Friday. Aleppo-based activist Mohammad Saeed said it was the largest demonstration there since the start of the uprising. He said more than 10,000 people protested in the Salaheddine and al-Shaar districts alone and thousands protested in other areas of the city. "The number of protesters is increasing every day and today saw the biggest protests," said Saeed, adding that several people were wounded when government forces tear gas and live ammunition to try and disperse the rally. The head of the British-based Syrian Observatory for Human Rights, Rami Abdul-Rahman, said the protest showed "it's a real uprising happening in Aleppo these days." Thousands of people across the country also staged anti-government rallies in solidarity with Aleppo. Friday is the main day of protests across Syria and this week's demonstrations were dubbed "The Heroes of Aleppo University" in solidarity with the students. Opposition activists said security forces opened fire in several other locations including the Damascus suburbs and the central city of Hama to disperse protesters and that the regime shelled the town of Rastan, which has been under the control of rebels since January. The violence comes as the head of U.N. observer team in Syria cautioned that unarmed force alone cannot stop the bloodshed without genuine talks between the two sides that have been locked in a violent conflict for more than a year. Maj. Gen. Robert Mood, the Norwegian head of the 200-strong observer team, warned Friday that no number of observers can achieve "a permanent end to the violence if the commitment to give dialogue a chance is not genuine from all internal and external actors." He spoke at a news conference in the Syrian capital, Damascus. International powers have pinned their hopes on a peace plan for Syria that special envoy Kofi Annan brokered in April. The plan paved the way for the U.N. observers, and it calls for a cease-fire and dialogue to stop 15 months of bloodshed. Hundreds more have been killed since then as a revolt that began in March 2011 with mostly peaceful calls for reform has transformed into an armed insurgency. Both sides have flouted the cease-fire, raising concerns that the peace plan is ineffective in a conflict where the violence is spinning out of control. Ahmad Fawzi, spokesman for Annan, said in Geneva that the envoy would be visiting Syria soon, but did not give a date. "We condemn in the strongest terms violence in all its forms by all parties," Fawzi said. This must come to an end for any political process to be launched and to have a glimmer of success. A high-ranking military adviser to U.N. Secretary Ban Ki-moon, Babacar Gaye, arrived in Damascus Friday. But dialogue seems a distant hope. The opposition refuses to engage with the regime while the killings continue, and the government brands its opponents as terrorists. Assad denies that there is a popular will behind the country's uprising, saying foreign extremists are driving the unrest to destroy the country. Two main activist groups, the Local Coordination Committees and the Observatory, said the opposition stronghold of Rastan again came under intense shelling as of Friday morning. Videos posted online showed thick smoke and shells slamming into districts in the town. "I am more convinced than ever that no amount of violence can resolve this crisis," Mood said in Damascus. He also said recent suicide bombs and roadside blasts were alarming. I am concerned about the incidents where explosives, improvised devices are targeting innocent civilians, innocent people because it is not going to help the situation. On Thursday, U.N. Secretary-General Ban Ki-moon said he believes that "alarmingly and surprisingly," al Qaeda must have been behind the massive attack in the Syrian capital last week. The twin suicide car bombings outside a military intelligence building on May 10 bore the al Qaeda-style tactics seen in neighboring Iraq. Some 55 people died and dozens were injured in the Damascus blasts. Ban said that al Qaeda's involvement in the region "has created very serious problems." He also noted that there have also been two attacks against unarmed U.N. monitors in Syria. His comments were made to students attending the annual Model U.N. Conference in New York.