Iraqi commandos backed by U.S. ground and air fire uncovered an apparent insurgent training camp today that hosted fighters from as far away as the Philippines, senior officials tell ABC News. The discovery was made after the members of Iraq's 1st Police Commando Battalion — who are part of the fighting forces of Iraq's interim government — were attacked while on a noontime patrol north of Baghdad, near Samarra. As they approached a group of buildings, they were attacked by sustained heavy fire from RPG, small arms, and mortars. Seven Iraqi commandos were killed and six were wounded. There were an estimated 70 to 100 attackers and they were in dug-in positions. A U.S. military officer with the unit called in air support. Attack helicopters from Task Force Liberty's Aviation Brigade responded but sustained major structural damage and were forced to turn back. More helicopters came in and fired on insurgents.Soldiers from the 1st Brigade Combat Team also responded in support. The U.S. military said an "undetermined number" of the attackers were killed," and no Task Force Liberty soldiers were reported killed or wounded. The fight lasted about 90 minutes. Once the insurgents broke contact, they fled by either boats back toward nearby Lake Tharthar or into local areas by vehicle or on foot. At the scene, the commandos found documents indicating that there were Syrians, Algerians, other Arabs and at least one Filipino among the insurgents. The "training camp" found nearby is being "exploited," officials said. On Monday and today, 20 insurgents were detained in three separate operations in Mosul, the military said in separate statements.