Four Royal Saudi Air Force (RSAF) Boeing F-15S fighter aircraft arrived Feb. 26 at Turkey’s Incirlik Air Base to support the U.S.-led coalition fighting the Islamic State in Syria, soon before a cease-fire is set to begin, AFP reported. Two RSAF Lockheed Martin C-130 Hercules transport aircraft carrying about 30 RSAF personnel and equipment previously arrived at Incirlik on Feb. 23. Saudi Arabia joins Germany, Qatar, the United Kingdom and the United States as one of five nations to deploy aircraft to the base for the anti-Islamic State mission. Nearly 100 rebel groups agreed Feb. 26 to abide by the U.N.-brokered cease-fire beginning Feb. 27, but fighting in the troubled region is unlikely to halt entirely.