Super typhoon Mangkhut bears down on millions in Philippines

Philippine authorities began evacuating thousands of people Thursday from the path of the most powerful typhoon this year, closing schools, readying bulldozers for landslides and placing rescuers and troops on full alert in the country's north.

More than 4 million people live in areas at most risk from the storm, which the Joint Typhoon Warning Center in Hawaii categorised as a super typhoon with powerful winds and gusts.

Typhoon Mangkhut could hit northeastern Cagayan province on Saturday.

It was tracked on Thursday about 725 kilometres (450 miles) away in the Pacific with sustained winds of 205 kilometres per hour and gusts of up to 255 kph, Philippine forecasters said.

With a massive raincloud band 900 kilometres wide, combined with seasonal monsoon rains, the typhoon could bring heavy to intense rains that could set off landslides and flash floods, the forecasters said.

Storm warnings have been raised in 25 provinces across the main northern island of Luzon, restricting sea and air travel.

Office of Civil Defense chief Ricardo Jalad told an emergency meeting led by Rodrigo Duterte, the president of the Philippines, that about 4.2 million people in Cagayan, nearby Isabela province and outlying provincial regions are vulnerable to the most destructive effects near the typhoon's 125-kilometre-wide eye.

Nearly 48,000 houses in those high-risk areas are made of light materials and vulnerable to Mangkhut's ferocious winds.

Across the north on Thursday, residents covered glass windows with wooden boards, strengthened houses with rope and braces and moved fishing boats to safety.

Cagayan Gov. Manuel Mamba said that evacuations of residents from risky coastal villages and island municipalities north of the rice-and corn-producing province of 1.2 million people have started and school classes at all levels have been cancelled.

"The weather here is still good but we're moving them now because it's very important that when it comes, people will be away from peril," Mr Mamba said.

A change in the typhoon's track prompted authorities to rapidly reassess where to redeploy emergency teams and supplies, Mr Mamba said.

Mr Duterte asked cabinet officials from the north to help oversee disaster-response work if needed, and told reporters it was too early to consider seeking foreign aid.