Cyclone Freddy battered central Mozambique on Sunday after making landfall for the second time in a month, breaking records for the duration and strength of tropical storms in the southern hemisphere.

Communications and power supplies in the storm area were interrupted, so the extent of damage and casualties were not clear.

More than 171,000 people were affected after the cyclone swept through southern Mozambique last month, killing 27 people in Mozambique and Madagascar. More than half a million people are at risk of being affected in Mozambique this time, according to the UN Office for the Coordination of Humanitarian Affairs (OCHA).

UNICEF said in a statement that Freddy came ashore with sustained winds of nearly 150 kilometers per hour (93 miles per hour), causing “severe damage and cutting children and families off from critical services.” After passing through the port city of Quelimane, the storm turned inland towards the southern tip of neighboring Malawi, satellite data showed.

However, the national energy company Electricidade de Moçambique said electricity had been restored to most areas by mid-afternoon, with the exception of Milange, Lugela, Maganja da Costa, Namanjavira and parts of the city of Mocuba.

“The wind was very strong late into the night… There is a lot of devastation, trees have fallen, roofs have been blown off,” said Guy Taylor, UNICEF’s chief of advocacy, communications and partnerships for Mozambique, via satellite phone from Quelimane to Reuters. He did not yet have a word on casualties or numbers of displaced people.

“It’s potentially a major disaster and additional support will be needed,” Taylor said, adding that heavy rains continued to fall.

In Malawi, authorities prepared for the cyclone to pass past the southern tip of the landlocked country by evening, bringing heavy rainfall and flooding, the Department of Meteorological Resources and Climate Change said in a statement.

Freddy developed off the northwest coast of Australia on February 6, before moving thousands of miles across the South Indian Ocean to Southeast Africa, hitting the islands of Mauritius and La Réunion along the way.

The storm hit the east coast of Madagascar on Feb. 21 before moving into Mozambique a few days later, bringing heavy rainfall, destructive winds and flooding that destroyed homes and affected nearly 2 million people.

It then looped back into the Mozambique Channel, drew energy from the warm waters and headed for Madagascar’s southwest coast.