Floodwaters reaching more than four meters high swamped thousands of houses in the storm-battered northern Philippines on Tuesday after rivers overflowed following heavy rain and a dam release.

More than a million people fled their homes ahead of Man-yi, which struck the Philippines as a super typhoon before significantly weakening as it swept over the mountains of the main island of Luzon.

Man-yi dumped heavy rain, smashed flimsy buildings, knocked out power and claimed at least eight lives.

Climate change is increasing the intensity of storms, leading to heavier rains, flash floods and stronger gusts.