At least 57 people were killed and many more feared trapped under debris following landslides and flooding triggered by heavy rainfall in northern Tanzania, the president and officials said on Monday.
"So far we have lost 57 of our brothers and sisters in this disaster, while 85 are still receiving treatment," said President Samia Suluhu Hassan, who cut short her visit to Dubai for the COP28 climate talks.
Heavy rain on Saturday hit the town of Katesh, some 300 kilometres (186 miles) north of Tanzania's capital Dodoma, the country's district commissioner, Janeth Mayanja said, adding the many roads in the area had been blocked by mud, water and dislodged trees and stones.
Tanzania's President Samia Suluhu Hassan, in Dubai for the COP28 climate conference, sent her condolences and said she had ordered the deployment of "more government efforts to rescue people".
Images broadcast on Tanzania's state television TBC showed many flooded homes and vehicles stuck in thick mud.
The downpours have displaced more than a million people in Somalia and left hundreds dead. In May, torrential rains caused devastating floods and landslides in Rwanda that killed at least 130 people.
Between October 1997 and January 1998, massive flooding exacerbated by heavy El Nino rains caused more than 6,000 deaths in five countries in the region. Scientists say extreme weather events such as flooding, storms, droughts and wildfires are being made longer, more intense and more frequent by human-induced climate change.