Taiwan has been pounded by raging winds and heavy rain brought by tropical typhoon Aere.
Rough seas have already killed five fishermen
At least five fishermen have reportedly drowned, while two residents in Taipei were injured by falling debris as winds uprooted trees and caused car crashes.
Typhoon Aere - whose name means "storm" in the Marshall Islands - was expected to dump up to 1,000mm (40in) of rain on the island.
A jetliner slid off a runway in Taipei, where offices and schools have closed.
The storm was also expected to strike the northern cities of Keelung and Hsinchu.
The authorities warned mountainous regions were at severe risk of flash-floods and landslides because of the heavy rains accompanying the storm.
A major war-game exercise set to have taken place on Wednesday had been cancelled, the military said.
Forecasters warn worse may yet be ahead if Typhoon Aere combines with another nearby storm, Typhoon Chaba, currently north of Guam and heading towards Japan.
That would create a "double-typhoon effect", prolonging Aere's destructive journey over Taiwan.
Three fishermen manning a Hong Kong fishing vessel are missing, presumed dead, after their vessel was overturned in the storm, the coast guard said.
The captain of their vessel was rescued but died later.
Another fishermen died when his small vessel was flipped over in the storm.
In Japan's Okinawan islands, high waves from the typhoon claimed the lives of two children who had been swimming in the sea.
The typhoon is expected to gradually move westwards, towards China.
Taiwan frequently bears the brunt of tropical storms and typhoons.
More than 20 people died last month when Typhoon Mindulle slammed into central and southern Taiwan.
The worst of the recent storms, Typhoon Toraji, killed some 200 people in 2001.