MARAWI, Philippines (AP) — Philippine military jets fired rockets at militant positions Saturday as soldiers fought to wrest control of a southern city from gunmen linked to the Islamic State group, witnesses said. The city of Marawi, home to some 200,000 people, has been under siege by IS-linked militants since a failed raid Tuesday night on a suspected hideout of Isnilon Hapilon, who is on Washington's list of most-wanted terrorists. Isnilon got away and fighters loyal to him took over parts of the city, burning buildings and seizing about a dozen hostages, including a priest. The violence prompted President Rodrigo Duterte to declare martial law in the country's south, where a Muslim rebellion has raged for decades. On Friday, Duterte ordered his troops to crush the militants, warning that the country is at a grave risk of "contamination" by the Islamic State group. In a sign that the long-standing problem of militancy in the south could be expanding, Solicitor General Jose Calida said foreigners were fighting alongside the gunmen in Marawi, including Indonesians and Malaysians. Hapilon, an Islamic preacher, is a commander of the Abu Sayyaf militant group who pledged allegiance to the Islamic State group in 2014.