A man braves the strong winds from Typhoon Soudelor with his bicycle in Taipei, Taiwan, Aug 8, 2015. [Photo/IC]

TAIPEI - Fatalities from Typhoon Soudelor have climbed to four, with another 27 injured and one missing in Taiwan, the island's authorities said.

The meteorological agency has warned that 15 cities and counties may experience extremely heavy precipitation of up to 350 mm or more in 24 hours, and the rest of the island could also see strong rainfall of 130 mm or more over the period.

All offices and schools across the island were closed on Saturday. Department store chains in Taiwan announced they will suspend business for at least Saturday morning. Saturday is Father's Day on the island and promoted as a shopping holiday.

High-speed rail lines and regular train networks have suspended services since early Friday afternoon. All airports on the island have also been closed, with returning flights forced to land in other cities, including Hong Kong and Osaka.

The center of Soudelor made landfall in Sioulin township in eastern Taiwan's Hualien county at 4:40 am, bringing with it strong gusts and torrential rain that cut the power supply for nearly a million households and filled cities with fallen trees and signboards, according to the Taiwan disaster operation center.

As of 6 am, Soudelor was centered 60 km west of Hualien, according to the center, and was moving northwestward at a speed of 19 kph. Giant waves of 8 to 11 meters high were seen along the island's eastern coast. The storm is packing maximum sustained winds of 173 kph, with gusts reaching 209 kph.

Forecasters said Soudelor could start weakening and move into the Taiwan Strait later in the morning following its current path, but warned that wind gusts and extreme rainfall could still be present.