The Rwandan military says its forces and Mozambican troops have retaken Mocímboa da Praia, a key port city from Islamist militants in northern Mozambique
Mocímboa da Praia located in Cabo Delgado province, was the rebels' last stronghold and home to one of Africa's biggest gas fields.
The insurgents have not yet commented but the news is seen as a major gain for Mozambique in its fight against insurgents in its north
Rwanda last month sent 1,000 soldiers to Mozambique to fight the militants, who launched an insurgency in 2017.
More than 3,000 people have been killed and 820,000 displaced during the conflict.
The Mozambican armed force which has been struggling to regain control of the province has been reluctant to seek foreign military help, but has now accepted help from its neighbours.
The southern African regional bloc, SADC, is sending in hundreds of troops, while former colonial power Portugal is on the ground instructing soldiers.
The forces last week claimed their first success since been deployed, saying they had helped the Mozambique army regain control of Awasse -- a small but also strategic settlement near Mocimboa da Praia.