MANILA (Reuters) - Nearly 60 people were killed, Manila was blacked out and airline flights were suspended as a powerful typhoon battered the main Philippines island of Luzon on Saturday, disaster officials said. Television showed houses swept away by swollen rivers, people on rooftops waving for help and throngs stranded along Manilas submerged main thoroughfares as the storm packing winds of 100 kph (60 mph) dumped 341 mm (13.5 inches) of rain in six hours. President Gloria Macapagal Arroyo appealed for donations of clothes, blankets, food and water as hundreds of families, perched on rooftops or were trapped in submerged areas, waiting for rescue. I am calling on our countrymen, especially residents of metro Manila and other provinces in the path of the typhoon, to please stay calm, follow the instructions of local officials and civil defence authorities, Arroyo said in a televised message. At least 47 people were killed, mostly by drowning, in Rizal province, east of Manila, radio reports quoted the local governor as saying. Eleven more people were killed by collapsing walls and rising floodwaters in the capital area, disaster officials said. Authorities shut down operations at international and domestic airports, stranding thousands of passengers. An advisory said operations would not resume until Sunday. Disaster officials declared a state of calamity for the capital region and 25 other areas on the main island of Luzon, in order to speed up rescue, relief and rehabilitation efforts. Businesses and commercial shops closed early and local hotels were packed by weary commuters. The typhoon was moving west-northwest and was expected to head towards the South China Sea by Sunday evening or Monday morning, chief weather forecaster Nathaniel Cruz told a local radio station. He said the typhoon brought the heaviest rainfall in the country since 1967 after its weather station collected 341 mm of rainfall in six hours on Saturday. An average of about 20 typhoons strike the Southeast Asian nation every year.