At least 46 people including children died when a makeshift dam burst its banks in Kenya's Rift Valley in the early hours of Monday, a local official said, as torrential rains and floods battered the country.

Scores of people have been killed over the March-May wet season in Kenya as heavier than usual rainfall pounds East Africa, compounded by the El Nino weather pattern.

Residents said the accident occurred in the dead of night when the dam burst near the town of Mai Mahiu in Nakuru county, sending torrents of water and mud gushing down a hill and engulfing everything in its path.

The deluge cut off a road, uprooted trees, washed away homes and sent vehicles flying, devastating the village of Kamuchiri.

"We heard what sounded like an earthquake and roars like a moving train," said Margaret Wangechi, a 52-year-old teacher.

Joyce Ncece, chief officer for disaster management in Nakuru County, said on Monday evening that there were 46 bodies at the mortuary, but warned that the number could increase.

The dead included 20 women and 17 children, she said.

Nakuru governor Susan Kihika said 110 people were being treated in hospital.

Rescuers dug through the debris, using hoes and in some cases just their bare hands in a desperate search for survivors.

"We collected some of the bodies held by trees and we don't know how many are under the mud," Stephen Njihia Njoroge, a local resident involved in the emergency efforts said.

The disaster occurred at Old Kijabe dam, a hillside barrier formed naturally over decades after railway construction work by Kenya's former British colonial rulers.

- 'Risky behaviour' -

The Red Cross has set up a desk at a local school to help families find lost loved ones.

Interior Minister Kithure Kindiki said the government had called for inspections of all dams and reservoirs within 24 hours in case there is a need for evacuations.

He also said on X that the authorities would arrest people engaging in "risky behaviour", including motorists attempting dangerous crossings and anyone seeking to transport "passengers across flooded rivers or storm water by unsafe canoes or boats".

His comments came after a crowded boat capsized at the weekend in flooded Tana River county in eastern Kenya.

Kindiki said two bodies had been found and 23 people rescued, and that search and rescue efforts were ongoing.

The Kenyan government spokesman said Monday that 103 people had lost their lives in floods since March, in a statement that did not mention the dam disaster.

More than 28,000 households have been displaced and over 185,000 people affected, the statement said.

The education ministry announced Monday it would postpone the reopening of schools following mid-term holidays to May 6 because of the rains.

- Turmoil across the region -

The weather has also wreaked havoc in neighbouring Tanzania, where at least 155 people have been killed in flooding and landslides.

In Ethiopia's capital Addis Ababa, flooding claimed the lives of four people on Monday, according to the Fire and Disaster Risk Management Commission.

A woman and her baby died in the Rwandan capital Kigali on Sunday when heavy rainfall caused their house to collapse, police said.

In neighbouring Burundi, one of the world's poorest countries, about 96,000 people have been displaced by months of relentless rains, according to the United Nations and the government.

Uganda has also suffered heavy storms that have caused riverbanks to burst, with two deaths confirmed and several hundred villagers displaced.

Monday's dam tragedy comes six years after a similar accident at Solai, also in Nakuru county, killed 48 people, sending millions of litres of muddy waters raging through homes and destroying power lines.

The May 2018 disaster involving a private reservoir on a coffee estate also followed weeks of torrential rains that sparked deadly floods and mudslides.

El Nino is a naturally occurring climate pattern typically associated with increased heat worldwide, leading to drought in some parts of the world and heavy rains elsewhere.

Late last year, more than 300 people died in rains and floods in Kenya, Somalia and Ethiopia, just as the region was trying to recover from its worst drought in four decades that left millions of people hungry.

The UN's World Meteorological Organization said in March that the latest El Nino is one of the five strongest ever recorded.