TUNIS (Agencies) - A fire swept through a prison in the Tunisian resort town of Monastir on Saturday, killing dozens amid continuing unrest following the removal of President Zine al-Abidine Ben Ali. Speaker of parliament, Fouad Mebazza, was sworn in as interim president. He asked Prime Minister Mohamed Ghannouchi to form a coalition government and the constitutional authorities said a presidential election should be held within 60 days. Looting hit the suburbs of Tunis after he fled the country on Friday. Troops were patrolling the city centre and a state of emergency was in force. Prime Minister Mohammed Ghannouchi said his priority is restoring order. He also said he would hold talks with Opposition parties. Eyewitnesses in Monastir said a fire had swept through a jail, killing dozens of inmates. The whole prison is on fire, the furniture, mattresses, everything, one witness told Reuters news agency. Forty-two people died in the Monastir riot, the official news agency said. In Tunis the main thoroughfare, Avenue Habib Bourguiba, was blocked off by security forces after curfew was lifted. Troops and tanks are protecting official buildings and the streets are largely deserted. Overnight looting continued into Saturday in the citys suburbs, with French-owned supermarkets among the properties targeted. Tunis main railway station has been damaged by fire. Tunis Carthage International Airport, which was closed amid Fridays unrest, re-opened on Saturday. Hundreds of tourists and other foreigners have been trapped there.