"It's an unprecedented event, extremely violent, the winds may exceed 180 kilometres (112 miles) per hour," Governor Francois-Xavier Bieuville said.

As the cyclone neared the territory, the authorities banned all 320,000 residents from moving.

Raising the highest alert "entails the strict confinement of the entire population, including rescue and security services and all officials mobilised for crisis management," the local government wrote on social media platform X.

The warning went into force at 7:00 am (0400 GMT), two hours before the eye of the storm was due to pass over northern Mayotte.

"This is serious. Mayotte has never known a situation like it," council chief Ben Issa Ousseni said Friday.

The authorities have turned more than 70 schools and gyms into shelters, with priority given to the 100,000 residents assessed as living in the most vulnerable homes.

"We're really scared," said Fatima, a resident of Majicavo-Koropa village on the eastern coast.

"I've stocked up on water bottles, food, candles," the 57-year-old told AFP.

At 6:00 am, the storm was about 100 kilometres northeast of Mayotte, weather service Meteo France said, forecasting "destructive or even devastating winds".

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