Sustained winds of more than 100mph have caused landslides, ripped off roofs and brought down trees in the Philippines as Typhoon Mangkhut pummeled northern areas of the country.
Two women died after a hillside collapsed in the city of Baguio, police said.
A woman also died in neighbouring Taiwan after being swept out to sea.
The storm, which gusted up to 160mph, knocked out power as it tore across the northern part of Luzon island – an area which is home to around 10 million people, many of whom live in flimsy wooden homes.
Thousands of evacuees have taken refuge in emergency shelters.
“We believe there has been a lot of damage,” social welfare secretary Virginia Orogo said.
“It’s still a life and death situation,” Defence Secretary Delfin Lorenzana said.
He added that Tuguegarao airport’s terminal roof and windows had been shattered, with the wind flipping chairs and tables around inside.