Cyclone Freddy, packing powerful winds and torrential rain, killed more than 100 people in Malawi and Mozambique on its return to southern Africa's mainland, authorities said Monday.
Freddy, on track to become the longest-lasting storm on record, barrelled through southern Africa at the weekend for the second time within a few weeks, making a comeback after a first hit in late February.
Malawi bore the brunt, counting at least 99 deaths after mudslides overnight washed away houses and sleeping occupants.
"We expect the number to rise," Charles Kalemba, a commissioner at the Department of Disaster Management Affairs, told a press conference.
Another 134 people were injured and 16 are reported missing.
Malawi's commercial capital Blantyre recorded 85 deaths.
Residents used their bare hands to dig through the mud hoping to find survivors.
Government rescuers were late to arrive, said one resident refusing to give his name, covered in mud, as he helped with the rescue effort.
"The people are overwhelmed. The situation is very difficult," said ambulance driver Honest Chirwa, adding rescuers lacked adequate equipment.
More than 11,000 people were affected by the storm, said the United Nations.
The impact of the cyclone has piled more woes on a country grappling with the deadliest cholera outbreak in its history, which has killed over 1,600 people since last year.
"Severe weather events such as these are likely to exacerbate the spread of waterborne diseases like cholera," the UN children's agency UNICEF warned.
President Lazarus Chakwera, currently in Doha attending a Least Developed Countries meeting, declared a "state of disaster in the Southern region" of the nation.
The government was responding to the crisis while appealing for local and international aid for affected families, his office said.
Malawi has ordered schools in ten southern districts to remain closed until Wednesday, with rains and winds expected to keep battering the nation's south.
At least 10 other people died and 14 were wounded in neighbouring Mozambique, local authorities said.
The Mozambique National Institute for Disaster Management said the fallout from the storm's second landfall in the country was worse than expected.
National carrier Malawi Airlines said all flights to Blantyre have been cancelled until further notice after an inbound plane ran into the bad weather and was forced back to the capital Lilongwe.
The country's energy utility also warned that electricity generation would be unstable, as it would have to temporarily shut down hydropower stations to prevent muddy water from damaging turbines.
Cyclone Freddy reached landlocked Malawi early on Monday morning after sweeping through Mozambique at the weekend.
According to the UN's World Meteorological Organization, Freddy, which formed off north-western Australia in the first week of February, was set to become the longest-lasting tropical cyclone on record.
It crossed the entire southern Indian Ocean and blasted Madagascar from February 21 before reaching Mozambique on February 24.
Following what meteorologists describe as a "rare" loop trajectory, Freddy then headed back towards Madagascar before moving once more towards Mozambique.
In total, Freddy has so far killed at least 136 people -- 99 in Malawi, 20 in Mozambique and 17 in Madagascar.
The last cyclones to cross the entire southern Indian Ocean were Leon-Eline and Hudah in 2000.