SHANGHAI (AFP) - Typhoon Soudelor moved towards China on Saturday, weaker but still packing a punch, after killing at least four people and leaving a trail of destruction in Taiwan.

The typhoon ripped up trees and triggered landslides in Taiwan, and knocked out power to 1.5 million homes. Rivers broke their banks under torrential rain and towering waves pounded the island's coastline.

In mainland China, which faces Taiwan across a narrow strait, at least 250,000 people have been evacuated from the coastal provinces of Fujian and Zhejiang ahead of the typhoon's arrival, which is forecast for Saturday evening.

Already, strong winds and heavy rain have cut off power and destroyed farm crops along China's eastern coast, state media reported.

"The tap water has stopped. The electricity is out. I'm hiding at home and scared to go outside," housewife Pan Danyun, who lives in Fujian's Fuzhou city, told AFP.

Taiwanese authorities said four people had died in the storm, including a firefighter in southern Pintung county and a man in the coastal town of Suao who was hit by a falling billboard.

An eight-year-old girl and her mother had become the first fatalities when they were swept out to sea and died as the storm approached on Thursday. The dead girl's twin was also missing in the same incident, while another nine-year-old girl was injured but survived.

Dramatic images showed an elderly man, buried up to his waist in another mudslide, being hauled out by emergency workers in the picturesque hot spring area of Wulai, just outside the capital Taipei.

Media reports said that he had died, but authorities were unable to immediately confirm his death.

There were also unconfirmed reports of another death in southern Kaohsiung, where a man was said to have been hit by a falling tree.

A total of four people were missing and more than 60 injured, Taiwan's Central Emergency Operation Centre said.

One mountain village in Taiwan's northern region of Taoyuan was left almost submerged in mud.

"Flash mudslides surged into the village. About 10 of the homes were half buried but people were evacuated last night and are in safe shelters," a spokesman for the Taoyuan fire agency told AFP.

Tatung township in eastern Yilan saw the most rain, with more than a metre falling since Thursday.

"I've never seen such a powerful typhoon in my 60 years of life," one elderly woman in eastern Taitung told Formosa TV.

China's National Meteorological Center (NMC) predicts Soudelor will make landfall on Saturday evening in Fujian, somewhere in a band roughly between the cities of Fuzhou and Xiamen.

Late Saturday afternoon, the typhoon was still around 125km from Fujian, it said.

"When it makes landfall in Fujian, it will be significantly weaker, basically the strength of a typhoon or severe tropical storm," the government agency's chief forecaster Qian Chuanhai told state television.

But Soudelor was still packing winds of up to 144kmh as it crossed the strait between Taiwan and mainland China.

Tens of thousands of households had lost power in Quanzhou city, state broadcaster CCTV reported, as it showed images of a devastated cucumber patch.

Billed as the biggest typhoon of the year earlier in the week, Soudelor - named after a legendary Micronesian chief - has since weakened.

Although authorities had warned it might strengthen before it hit Taiwan, wind speeds near its centre remained at 173kmh as it made landfall early Saturday.

But Chinese authorities are taking no chances. More than 300 trains linked to Fujian have been cancelled, while China's three biggest airlines have also scrapped more than 60 domestic flights.

Fujian and Zhejiang provinces had ordered nearly 60,000 fishing boats to return to port, according to local officials.

The typhoon has already dumped more than 200mm of rain in just over 24 hours in some areas along China's eastern coast.

Chinese forecasts show it moving inland to the central province of Jiangxi after making landfall.

"Soudelor will continue to deteriorate as it makes a final landfall in China," the US military's Joint Typhoon Warning Centre said. "As the system tracks further inland it will erode rapidly."