The strongest typhoon in the world this year and possibly the most powerful ever to hit land smashed into the Philippines
More than one million people were forced to flee, villages were flood and there are fears of widespread casualties.
Haiyan, a category-5 super typhoon, scoured the northern tip of Cebu province and headed northwest towards Boracay island, both tourist destinations.
It earlier lashed the central islands of Leyte and Samar with 275km/h wind gusts and five to six metre waves.
At least three people were killed and seven injured, national disaster agency spokesman Rey Balido told reporters in Manila.
The death toll could rise as more reports arrive.
"The humanitarian impact of Haiyan threatens to be colossal," Patrick Fuller, spokesman for the International Federation of Red Cross and Red Crescent Societies said.
Power and communications in the three large islands of Samar, Leyte and Bohol were almost completely down but authorities promised to restore them within 24 hours.
Officials warned that more than 12 million people were at risk, including residents of Cebu City, which has a population of about 2.5 million, and areas still reeling from a deadly 2011 storm and a 7.2-magnitude quake last month.
"The super typhoon likely made landfall with winds near 195mph (313km/h). This makes Haiyan the strongest tropical cyclone on record to make landfall," Jeff Masters, director of meteorology at US-based Weather Underground said.
About 1m people took shelter in 29 provinces, after President Benigno Aquino appealed to people in Haiyan's path to leave vulnerable areas, such as river banks, coastal villages and mountain slopes.
Energy Secretary Jericho Petilla reported a three metre flood in one village in Leyte.
More than 100 coastal homes were flattened, while landslides destroyed houses in the hills, but his province had seen no casualties yet, Roger Mercado, governor of Southern Leyte province said.
In Samar province, links with some towns and villages had been cut, officials said.
"The whole province has no power," Samar Governor Sharee Tan said. Fallen trees, toppled electric poles and other debris blocked roads, she added.
Authorities suspended ferry services and fishing and shut 13 airports. Nearly 450 domestic, and eight international, flights were suspended.
Schools, offices and shops in the central regions were shut, with hospitals, soldiers and emergency workers preparing rescue efforts.
Twenty navy ships and military aircraft including threeC-130 cargo planes and helicopters were on standby.
The state weather bureau said Haiyan was expected to movepast the Philippines tomorrow and out over the South China Sea, where it could strengthen even further and hit Vietnam.
Meteorologists in Vietnam said it could be the country's strongest storm ever. Evacuations had already begun, the state-run Voice of Vietnam radio said.
The world's strongest recorded typhoon, cyclone or hurricane to make landfall was Hurricane Camille in 1969, which hit the southern US state of Mississippi with 305km/h Weather Underground's Masters said.
An average of 20 typhoons hit the Philippines every year.
Last year, Typhoon Bopha flattened three towns on Mindanao, killed 1,100 people and caused damages of more than $1 billion.
Haiyan is the second category 5 typhoon to hit the Philippines this year after Typhoon Usagi in September.