Fung-wong, with a footprint that spanned nearly the entire archipelago, slammed into the eastern seaboard as a "super typhoon" on Sunday evening, uprooting trees and swamping towns in its path.

It landed days after Typhoon Kalmaegi swept through the islands of the central Philippines, killing at least 224 people.

Cleanup efforts were underway on Monday from Cagayan province in the far north to hard-hit Catanduanes island more than 1,000 kilometres (620 miles) to the south.

In Cagayan, provincial rescue chief Rueli Rapsing told AFP a flash flood in neighbouring Apayao province had caused the Chico River to burst its banks, sending nearby residents scrambling for higher ground.

"We received reports around six in the morning ... that some people were already on their roofs," he said.

While most had been rescued, video verified by AFP showed that some were still trapped.

More than 5,000 people were safely evacuated before the overflowing Cagayan River buried the small city of Tuguegarao about 30 kilometres away.

"Tuguegarao is underwater now," Rapsing said.

Schools and government offices across the main island of Luzon were closed on Monday. That included the capital Manila, where residents were cleaning up after a night of heavy rain.

In Aurora province, rescue worker Geofry Parrocha said officials were assessing the damage.

"We're seeing many damaged houses and some of our main roads were not passable due to landslides," he told AFP from Dipaculao town, where power had yet to be restored.

"We couldn't mobilise last night because the rain was heavy and the volume of water was high."

- 'The ground was shaking' -

Samar province, hammered by Typhoon Kalmaegi last week, recorded the first known death from Fung-wong on Sunday.

Rescuer Juniel Tagarino told AFP the body of a 64-year-old woman who had been trying to evacuate was pulled from under debris and fallen trees in Catbalogan City.

"The wind was so strong and the rain was heavy... According to her family members, she might have forgotten something and gone back inside her house," Tagarino said.

The civil defence office later confirmed a second death, a person who drowned in a flash flood on Catanduanes island.

Storm surges sent waves hurtling over streets and floodwaters inundating homes in some areas of Catanduanes.

"The waves started roaring around 7:00 am. When the waves hit the seawall, it felt like the ground was shaking," resident Edson Casarino, 33, told AFP.

Video verified by AFP showed a church in Virac town surrounded by floodwaters that reached halfway up its entrance.

There was also major flooding in southern Luzon's Bicol region, where verified video showed streets transformed into raging torrents of water.

More than 1.4 million people nationwide were evacuated in the face of the storm.

- Taiwan in sights -

Fung-wong is now turning towards Taiwan, where it is expected to bring torrential rain to the north and east as it intensifies the seasonal northeast monsoon, Taipei's Central Weather Administration said.

More than 350 millimetres (14 inches) of rain is expected in a 24-hour period across the region, forecaster Stan Chang told AFP.

Nearly 5,000 people will be evacuated from their homes in three townships in the eastern county of Hualien, said local government official Lee Kuan-ting.

The townships are near a barrier lake that burst, killing 19 people, during torrential rain brought by Super Typhoon Ragasa in September.

- A state of 'calamity' -

Typhoon Kalmaegi sent floodwaters rushing through the towns and cities of the central Philippines last week, sweeping away cars, riverside shanties and shipping containers.

Search-and-rescue efforts in hardest-hit Cebu province were suspended at the weekend as Typhoon Fung-wong approached.

President Ferdinand Marcos said on Monday that a "state of national calamity" connected to Kalmaegi would be extended to a full year.

Scientists warn that storms are becoming more powerful due to human-driven climate change. Warmer oceans allow typhoons to strengthen rapidly, and a warmer atmosphere holds more moisture, meaning heavier rainfall.