Winds of up to 230 kilometres (143 miles) per hour battered the territory of 900,000 people and the storm earlier forced the closure of the main airport on nearby Mauritius.

Residents posted pictures online of uprooted trees, torn-off roofs and flooded homes on La Reunion.

Power outages affected around 145,000 people across the island, while 82,000 had no drinking water and 39,000 were without internet access, authorities said.

Authorities imposed a maximum "purple alert" for several hours early Friday, confining the entire population -- including law enforcement and emergency services -- to homes and offices.

This was eased at midday (0800 GMT) so that police and emergency services could get out but authorities still ordered the rest of the population to remain indoors.

Garance landed on the island's north and barrelled south. Weather service Meteo France said it would take up to three hours for the cyclone to cross La Reunion and head out to sea again.

While the violent gusts and intense rainfall and sea swells eased, heavy rain and strong winds persisted. "The red alert continues, and mandatory confinement remains in force," the prefecture authorities said in a post on X that signalled the worst weather was over.

- 'First time I've been afraid' -

Residents said the force of the cyclone was frightening.

"This is the first time I've seen a cyclone this powerful, and also the first time I've been afraid," said Vincent Clain, 45, who lives in Sainte-Marie on the northern coast.

He told AFP by telephone that the storm had uprooted trees in his garden. "I thought they would crash onto the house," he said.

Clain, his wife, their son and dog hid in their kitchen, "the safest area of the house".

Aline Etheve, a resident of Sainte-Suzanne on the coast, said she was worried the roof of her house would collapse after the storm destroyed her garden fence.

"I must admit I'm a little scared," she told AFP, adding that her power and wifi access were gone.

There were no immediate reports of deaths, the prefecture said. But close to 700 people found shelter in emergency structures across the island.

- 'Extremely vigilant' -

Around 100 troops and firefighters were to be dispatched from Mayotte -- a French territory nearly 1,500 kilometres away -- as soon as weather conditions permit. Another 100 were poised to travel to La Reunion from mainland France.

La Reunion and Mauritius -- around 225 kilometres (140 miles) to the northeast -- had been on high alert since Wednesday.

Mauritius shut its main airport on Wednesday, while La Reunion did the same on Thursday.

"Faced with cyclone Garance, I call on our fellow citizens of Reunion Island to be extremely vigilant and to respect safety instructions," President Emmanuel Macron posted on X late Thursday.

In the capital Saint-Denis, residents had scrambled to stock up on essentials before the purple alert was issued.

Farmers dismantled greenhouses to prevent their destruction, while fishermen pulled boats onto land. "It is a feeling of being powerless," said Jean-Christophe Hoareau, a farmer.

Cyclone Belal killed four people on La Reunion in January 2024.

burs/jh/tw