Monster typhoon Haiyan, locally known as Yolanda, roared into the Philippines with winds of over 275km/h, threatening to turn into the world's most powerful tropical cyclone in the next few hours.
The cyclone, a category-five storm, hit shore at 04:40 local time over Guiuan, having intensified and accelerated in the hours before landfall.
Yolanda has so far made at least five separate landfalls in the southeast Asian nation and is poised to batter the country further.
The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) said the cyclone has slightly weakened following the landfall but has gained speed. The menacing superstorm is threatening to inflict damage in vast areas across its path, which are already reeling from a recent earthquake.
The US Navy's Joint Typhoon Warning Centre in Hawaii said Yolonda is the world's strongest typhoon this year.
Philippine authorities had already ordered thousands to be evacuated while schools remained closed in vulnerable regions.
At least one fatality has been reported where a 56-year-old man was electrocuted. Authorities said this was an isolated incident.
The storm is expected to move past the Philippines later in the day towards the West Philippine Sea.
"To our local officials, your constituents are facing a serious peril. Let us do all we can while (Haiyan) has not yet hit land. We can minimise the effects of this typhoon if we help each other. Let us remain calm, especially in buying our primary needs, and in moving to safer places," President Benigno Aquino said in the televised address.
Below are the areas in the Philippines listed under public storm signal No: 4, the category under which winds of at least 185km/h will be felt:
Southern Occidental Mindoro
Southern Oriental Mindoro
Calamian Group of Island
Northern Negros Occidental