A tropical cyclone that swept across Mozambique at the weekend may have killed more than 1,000 people, President Filipe Nyusi said as heavy rains continued to pound neighboring Zimbabwe where flooding left dozens more dead.

“It’s clear that the next few days could be worse,” Nyusi said in comments broadcast on state radio. “If more than 1,000 lives have been lost, we won’t be surprised.”

The death toll has risen sharply since Tropical Cyclone Idai made landfall almost directly over the Mozambican port city of Beira on Friday, knocking out communications networks and power plants before moving westward to Zimbabwe. The scale of the damage wrought by the storm is “massive and horrifying,” said Jamie LeSueur, who is leading an International Federation of Red Cross and Red Crescent assessment team in Beira.

“It seems that 90 percent of the area is completely destroyed,” he said in a statement.

Eskom Holdings SOC Ltd., the state-owned power utility in neighboring South Africa, said the storm reduced the amount of electricity it imports from the Mozambique’s Cahora Bassa hydropower dam, exacerbating a shortage that’s resulted in blackouts.

Zimbabwean President Emmerson Mnangagwa cut short a visit to the United Arab Emirates to manage the government’s response to the disaster, the state-owned Herald newspaper reported. Nyusi also ended a trip to neighboring Eswatini ahead of schedule to tour some of the worst-hit areas in central parts of the country.

Heavy rains are forecast to continue into the middle of the week, bringing more flooding and making it difficult to reach stranded communities in both Mozambique and Zimbabwe.

“We hope that the weather will improve, but right now we only have one helicopter on the ground which is operating in the area due to bad weather,” Joshua Sacco, a Zimbabwean lawmaker for Chimanimani East, one of the worst-affected areas, said by phone. “Unfortunately indications are that the death toll will increase. It’s not looking good at all.”

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