The armies of these two groups, ZAPU's Zimbabwe People's Revolutionary Army (ZIPRA), and ZANU's Zimbabwe African National Liberation Army (ZANLA), developed rivalries for the support of the people and would fight each other. When Rhodesia became Zimbabwe in 1980, following the Lancaster House Agreement, the two armies so distrusted each other that it was difficult to integrate them both into the National Army. These problems were only in Matabeleland. For example: former ZIPRA elements attacked civilian areas in Zvishavane, Kadoma and Bulawayo. It seemed ZIPRA had a hidden arms cache. There were major outbreaks of violence carried out by ZIPRA against the civilian population . The first of these was in November 1980, followed by a more serious incident in early 1981. This led to the defection of many ZIPRA members. ZAPU was supporting a new dissident war to improve its position in Zimbabwe. In the elections held in April 1980, ZANU received 57 out of 100 seats and Robert Mugabe became prime minister.