In late 1978, the Uganda–Tanzania War broke out and the armed Ugandan opposition movements rallied to fight alongside the Tanzanians against Amin's regime. At the time, FRONASA had just 30 armed members. After the Tanzania People's Defence Force (TPDF) defeated the Ugandan invasion of Kagera, it counterattacked into Uganda. FRONASA guerrillas consequently acted as scouts for the Tanzanian 206th Brigade, aiding it during the capture of Mbarara. In March 1979, the Tanzanian government organized the Uganda National Liberation Front (UNLF) and its armed wing, the Uganda National Liberation Army (UNLA). The UNLF/UNLA was supposed to serve as umbrella organization to unify all Ugandan rebel factions, including FRONASA. Regardless of this nominal unification, the UNLF was split into numerous sub-units according to the wishes and needs of the Tanzanian military. Following the Fall of Kampala and overthrow of Amin's regime in April 1979, Museveni became Minister of Defence in the new Tanzanian-backed UNLF government of Uganda. FRONASA consequently acted as his private army and he recruited a large number of Tutsi and Banyankole to bolster its ranks. The group was about 9,000 to 10,000 fighters strong at its peak by mid-1979. As result of recruiting many Tutsi who were refugees from Rwanda, FRONASA became aligned with the newly founded Rwandese Alliance for National Unity, an organization that aimed at creating an army of Tutsi exiles to overthrow the government of Rwanda. From April 1979, however, Museveni had left the frontlines to involve himself in politics in Kampala.