More than 700 people have been confirmed dead as a result of Cyclone Idai, officials said.
Across Mozambique, Zimbabwe and Malawi the death toll has risen to 732, government and United Nations said.
The storm has wreaked havoc after battering the Mozambican port city of Beria on March 14, before moving inland towards Zimbabwe and Milawe.
Homes have been flattened during the storm, as well as road and bridges damaged.
Rescue workers are now starting the desperate search for people, as well as trying to help hundreds more.
Cases of cholera have been reported in Beira, adding the danger of deadly illnesses to people who are scrambling to find food, water and shelter, the International Federation of the Red Cross and Red Crescent Societies said.
"We'll have cholera for sure," Environment minister Celso Correia said, though no cases have yet been confirmed.
Heavy rains also washed away agricultural lands, leaving many with nothing to harvest.
On Mozambique the death toll currently stands at 417, with 1,400 feared injured. In Zimbabwe, 259 have been killed and 200 injured, and in Malaqi 56 have been killed, with 577 injured.
Sebastian Rhodes Stampa, deputy director of the UN Humanitarian operation, called the scale of the devastation "extraordinary" - not only because of the cyclone and flooding but the fact that the land already had been saturated by earlier rains.
A huge number of aid assets are now in Mozambique, Mr Stampa said.
"No government in the world can respond alone in these circumstances," he said.
