Torrential downpours at the weekend washed away vehicles and brought down buildings in the hillside town of Katesh, some 300 kilometres (186 miles) north of the capital Dodoma.
“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.
On Sunday, regional commissioner Queen Sendiga said there were 47 dead.
Search and rescue operations were underway with the help of the military as people were feared trapped or buried in thick mud, said Prime Minister Kassim Majaliwa, who visited the town.
Images broadcast on television showed debris from houses, including furniture, strewn across streets, with key roads, power lines and communication networks disrupted.
Paschal Paulo, a resident of the area, said everything had been washed away in the market where he worked.
James Gabriel, who also worked at the market, said his relatives were missing and the search was “very stressful.”
Esther Bohay said she heard loud noises and saw the streets outside her home turn into a river of mud as the rain swept in.
She managed to escape the deluge with her family.
At least 100 houses were swallowed by the mud and a village with 28 families flattened, said Sendiga.
An official in the prime minister’s office, Jenista Mhagama, said “more bodies” were being recovered from the wreckage, without elaborating.
Tanzania and its East African neighbours Kenya, Somalia and Ethiopia are battling flash floods caused by torrential rains linked to the El Nino weather pattern.
The floods are exacerbating the humanitarian crisis in the region just as it emerges from the worst drought in four decades that left millions of people hungry.
Between October 1997 and January 1998, massive flooding aggravated 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.
