Nearly a million people in the Philippines were evacuated from their homes Saturday as the most powerful typhoon of the year so far barrelled towards the country, with authorities warning of "destructive" winds and flooding.

At least 26 fishermen were missing at sea as one of the strongest typhoons in two decades tore into Vietnam's central coastline on Wednesday, uprooting trees and forcing hundreds of thousands into shelter.

Flood-ravaged Vietnam has begun evacuating more than half a million people from its central coastal region as it braces for Typhoon Molave, the fourth storm to hit the country in weeks.

A strong typhoon lashed the southern part of the Philippines' main Luzon island overnight, dumping heavy rains, toppling power lines and leaving at least 12 fishermen missing on Monday, disaster officials said.