(Adds details) By Lee Chyen Yee TAIPEI, Aug 18 (Reuters) - Typhoon Sepat lashed Taiwan with strong winds and torrential rain on Saturday, cutting power supplies to nearly 57,000 homes, injuring 12 people and forcing more than a thousand others to evacuate, before ploughing on towards China. In China's coastal areas, hundreds of thousands of people had to be evacuated and flights were cancelled due to the typhoon, which had already caused flooding in the Philippines. In Taiwan, two vehicles were crushed by a falling billboard in Taipei, scaffolding collapsed at a building in the outskirts of the city and workers battled to clear uprooted trees that were blocking roads and repair snapped power cables. "We were so busy yesterday because customers were grabbing instant noodles and other things from our shelves to stock up food for the typhoon today," Alice Wu, a shopkeeper at a convenience store in Taipei aged in her 20s, told Reuters. "Things are quieter today because everybody is staying indoors. Almost all the shops around here are closed, except for us." About 57,000 homes in Taiwan were still suffering from power outages, after repairs were done in most of the nearly 305,000 homes that had no electricity, according to the disaster centre. Taiwan Premier Chang Chun-hsiung urged Taiwanese to be vigilant of the impact from the typhoon, even though the storm was slowly departing, according to a government statement. HEADING FOR CHINA The eye of the storm had already passed over Taiwan's main island. Sepat -- a Malay name for a freshwater fish -- was heading towards China, where nearly 300,000 people in the eastern province Fujian and another 170,000 in Zhejiang province were evacuated, Xinhua said. The typhoon was due to make landfall in Fujian at around 1100 GMT, China's Xinhua news agency quoted weather officials as saying. In Fujian, officials were told to cancel their holidays to make emergency preparations for the storm, with flights from its cities cancelled since Saturday morning, media reports said. At 1000 GMT, the centre of the typhoon was around 60 km (37 miles) north of the offshore Penghu islands located in Taiwan's west, Taiwan's Central Weather Bureau said. It packed sustained winds of 126 km (78 miles) per hour and gusts up to 162 km (101 miles) per hour but was gradually losing strength, having been downgraded to a category 3 "medium typhoon" from a category 5 "super typhoon", a bureau official said. Twelve people were injured in Taipei city in the north and Kaohsiung county in the south, while another 1,785 people had to evacuate from their homes in Taiwan, according to the National Fire Agency, Taiwan's disaster centre. Officials at the centre said one person had died and another was injured while driving in bad weather on Friday, but the case was considered a road accident and not a storm-related casualty. Some flights from Taipei and Kaohsiung, Taiwan's two biggest cities, were either postponed or cancelled. Flights affected were mainly bound for Hong Kong, Macau and other Asian cities. In the Philippines, where Sepat exacerbated monsoon rains, nearly 390,000 people had been affected by flooding in Manila and northern provinces and more than 2,500 people were being housed in evacuation centres, disaster officials said. "We are praying hard for the rains to stop so our lives can go back to normal," said Ricardo Quito, 54, who had been camping with his family in a public market. "What we need now are medicines, foods and clothing. Our children are getting sick because of the unsanitary environment here." (Additional reporting by Ralph Jennings in Taipei, Carmel Crimmins in Manila and John Ruwitch in Hong Kong)
