In 1974, 12 MiG-21Bis were obtained from the Soviet Union, with a pair of two-seat MiG-21UMs to follow a couple of years later. These initial Fishbeds served alongside the four remaining MiG-17Fs and saw combat on two occasions during the Agacher Strip War in 1974 against Upper Volta, and again in 1985 with the same country, now renamed Burkina Faso. In 2005, another three MiG-21MFs were delivered from the Czech Republic, reinforcing the surviving jets. By 2010, the Fishbeds were only flown on ceremonial occasions. By January 2012, only one MiG-21MF and one MiG-21UM remained operational until they were grounded for lack of spare parts, ammunition, and pilots a few months later. In January 2013, the Nigerian Air Force sent a technical team to Bamako–Sénou International, with the aim of refurbishing the MiG-21s, but the project was abandoned. Other jets withdrawn from service were six L-29 Delfins, which were used for training.