Nearly 750,000 people were forced to flee their homes and damage was believed to be extensive.
Weather officials said Haiyan had sustained winds of 235 kph (147 mph) with gusts of 275 kph (170 mph) when it made landfall. By those measurements, Haiyan would be comparable to a strong Category 4 hurricane in the U.S., nearly in the top category, a 5.
Hurricanes, cyclones and typhoons are the same thing. They are just called different names in different parts of the world.
Because of cut-off communications in the Philippines, it was impossible to know the full extent of casualties and damage. Officially, four people were listed as dead as of Saturday morning, before the latest information from Tacloban came in.
Southern Leyte Gov. Roger Mercado said the typhoon ripped roofs off houses and triggered landslides that blocked roads.
The dense clouds and heavy rains made the day seem almost as dark as night, he said.
"When you're faced with such a scenario, you can only pray, and pray and pray," Mercado told The Associated Press by telephone, adding that mayors in the province had not called in to report any major damage.
"I hope that means they were spared and not the other way around," he said. "My worst fear is there will be massive loss of lives and property."
Eduardo del Rosario, head of the disaster response agency, said the speed at which the typhoon sliced through the central islands — 40 kph (25 mph) — helped prevent its 600-kilometer (375-mile) band of rain clouds from dumping enough of their load to overflow waterways. Flooding from heavy rains is often the main cause of deaths from typhoons.
"It has helped that the typhoon blew very fast in terms of preventing lots of casualties," regional military commander Lt. Gen. Roy Deveraturda said. He said the massive evacuation of villagers before the storm also saved many lives.