Dozens more people were confirmed killed in other flattened towns and cities across a 600-kilometer stretch of islands through the central Philippines. The Philippines endures a seemingly never-ending pattern of deadly typhoons, earthquakes, volcano eruptions and other natural disasters. This is because it is located along a typhoon belt and the so-called Ring of Fire, a vast Pacific Ocean region where many of Earth's earthquakes and volcanic eruptions occur.
However, if the feared death toll of above 10,000 is correct, Haiyan would be the deadliest natural disaster ever recorded in the Philippines.
The previous deadliest disaster in the Philippines occurred in 1976, when a tsunami triggered by a magnitude 7.9 earthquake devastated the Moro Gulf on the southern Philippine island of Mindanao, killing between 5,000 and 8,000 people.
Haiyan's maximum sustained wind speeds made it the strongest typhoon in the world this year, and one of the most powerful ever recorded.
Witnesses in Tacloban recalled waves up to five meters (16 feet) high surging inland, while aerial photos showed entire neighborhoods destroyed with trees and buildings flattened by storm surges that reached deep inland.
"The effects are very similar to what I have seen in a tsunami rather than a typhoon," the Philippine country director of the World Food Programme, Praveen Agrawal, who visited Tacloban, told AFP. "All the trees are bent over, the bark has been stripped off, the houses have been damaged. In many cases they have collapsed."
President Benigno Aquino said while visiting Tacloban that looting had emerged as a major concern, after only 20 out of 390 of the city's police officers turned up for work following the typhoon. "So we will send about 300 police and soldiers to take their place and bring back peace and order," he told reporters in Tacloban. "Tonight, an armored vehicle will arrive and our armed forces will display the strength of the state to put a stop to this looting."
As the scale of the disaster began to emerge, an international aid effort began to ratchet up. In Washington, the Pentagon announced that US Defense Secretary Chuck Hagel had responded to a request from the Philippines for military aid and directed the US Pacific Command to deploy resources. United Nations leader Ban Ki-moon also promised that UN humanitarian agencies would "respond rapidly to help people in need", while the European Commission said it would give three million euros ($4 million) to help in relief efforts.
Haiyan moved out of the Philippines and into the South China Sea on Saturday, from where it tracked towards Vietnam. Although it weakened out at sea, more than 600,000 people were evacuated in Vietnam ahead of its expected landfall on Monday morning.
Chinese state news-agency Xinhua meanwhile reported six members of a cargo boat were missing off the southern island province of Hainan.