More than 430 are dead and many others missing after Tropical Storm Washi hit the southern Philippines, officials have confirmed.

An army spokesman told the BBC that heavy rain from Washi brought water that swept many villagers on the north coast of Mindanao island into the sea. The cities of Iligan and Cagayan de Oro have taken the hardest hit, the BBC reported, noting that many people were asleep when the flood waters crept into their homes.

Authorities said the massive flood has forced tens of thousands of people to flee to safety.

USA Today reported that floodwaters rushed down from the mountains after 12 hours of rain.

Ayi Hernandez, a former congressman, told the media that he and his family were at home in Cagayan de Oro when they heard a loud swooshing sound. They found themselves in ankle-deep water inside their homes and decided to evacuate to a neighbor's two-story house, according to the USA Today report.

It was a good thing, because in less than an hour the water rose to about 11 feet (3.3 meters), filling his home up to the ceiling, he said.

Benito Ramos, who heads national disaster rescue agency, told the BBC that the floodwaters quickly rose overnight on Friday.

Massive flooding had been reported over the region, especially in Iligan City and Cagayan de Oro City, he said

After the 12 hours of rain, rivers swelled and burst their banks.

Philippine National Red Cross Secretary General Gwen Pang told the BBC that at least 430 people were killed -- 215 killed in Cagayan de Oro and 144 in Iligan.

Pang told The Associted Press that those figures were based upon the numbers of bodies brought to funeral parlors.

Col. Leopoldo Galon, a military spokesman has said that approximately 10,000 soldiers were conducting rescue efforts in Cagayan de Oro and along the north shore of Mindanao.

I can't explain how these things happened, he told the BBC. Entire villages were swept into the sea by flash floods.

Galon said he has never seen anything like what happened before, stating that Washi could be worse than Ondoy, which struck in 2009. That storm flooded Manila and claimed more than 400 lives.

Start the slideshow to see photos of the damage.