AMMAN: Syrian security forces sealed off the coastal city of Banias overnight following pro-democracy protests and killings by irregulars loyal to Syrian President Bashar Al-Assad, witnesses said on Monday. In the capital, students demonstrated at Damascus University's science college to express solidarity with protesters killed over the weekend, students on the campus said. One activist said he received text messages saying security forces had killed one student and surrounded the campus. But a pro-government Facebook page said security forces “took control of the security breach”, adding that there were no casualties. Assad, facing unprecedented protests against his 11-year-rule, has responded with a mixture of force and promises to move towards reform, including a possible lifting of nearly five decades of emergency law. Violence in Banias, home to one of Syria's two oil refineries, erupted on Sunday when irregulars from the ruling Alawite minority, known as “shabbiha”, fired at residents with automatic rifles from speeding cars, the witnesses said. Four people were killed in the mostly Sunni Muslim city on the Mediterranean coast, the Syrian Observatory for Human Rights said. Authorities said an armed group had ambushed a patrol near Banias, killing nine soldiers. Activists and protesters said roads to Banias were blocked. “Electricity has been cut since yesterday. People are very afraid,” Anas Al-Shughri, one of the protest leaders, told Reuters from Banias. “The army has deployed in Banias with infantry and they have set up checkpoints in and around the city.” Assad has said the protests are part of a foreign conspiracy to sow sectarian strife. His father, the late President Hafez al-Assad, used similar language when he crushed leftist and Islamist challenges to his rule in the 1980s, killing thousands. Civic leaders and opposition figures reject the allegation and issued a declaration last month denouncing sectarianism, committing to non-violent democratic change and stating that Syria's people “as a whole are under repression”. The protests have spread across Syria despite Assad's attempts to defuse resentment by making gestures towards demands for an end to an emergency law and to appease minority Kurds and Sunni Muslims. With popular dissent now in its fourth week, security forces fanned out in tanks on Saturday night near the Banias oil refinery, close to the Alawite district of Qusour where the main hospital is located. Gunfire could be heard across the city on Sunday. “The streets have emptied following the killings. People are afraid. The shabbiha fired at random and you can see bullet holes on buildings,” a human rights activist in Banias said. At least 90 people in Syria have been killed in mass demonstrations, which first erupted in March to demand the release of schoolchildren who scrawled pro-democracy graffiti on school walls in the southern city of Deraa, and later progressed to calling for freedoms and an end to Assad's rule. Any political change in Syria would have wider repercussions because the ruling Assad family maintains an anti-Israel alliance with Iran and supports the militant Hezbollah and Hamas movements while also seeking a peace deal with the Jewish state. The West has condemned Syria's use of violence but diplomats say it is unlikely that Syria will face the kind of intervention seen in Libya, unless killings reach the scale of the 1980s.