LARAF Soviet-made MiG-17/19/25 fighters and Tu-22 bombers were based at Okba Ben Nafi Air Base. After the 1969 seizure of power by Colonel Gaddafi, aircraft and personnel of the Soviet Air Force took residence at Okba Ben Nafi Air Base. With Soviet assistance, the Libyan Arab Republic Air Force was organized into one medium bomber squadron with Tupolev Tu-22s, three fighter interceptor squadrons, five forward ground attack squadrons, one counter-insurgency squadron, nine helicopter squadrons, and three air defense brigades deploying SA-2, SA-3, and Crotale missiles. Of the combat aircraft, the United States Department of State estimated in 1983 that 50 percent remained in storage, including most of the MiG fighters and Tu-22 bombers. In 1971, 11 civilian C-130s were delivered by the United States and converted in Italy to military versions. Four L-100-30s were purchased from the Philippines and Luxembourg in 1981. In 1976, 20 CH-47 Chinook heavy transport helicopters were acquired from Italy, 14 of which were transferred to the army during the 1990s. Libya also received 53 Dassault Mirage 5D and 32 5DE from France along with 15 5DD and 10 5DR followed by 16 Dassault Mirage F1AD, 6 F1BD & 16 F1ED aircraft.