(CNN) Extreme weather is striking parts of Asia with deadly flash-flooding in Vietnam, a tropical storm prompting evacuations and disrupting travel in China and an ongoing heat wave in Japan.

In Vietnam, 21 people have died and more people are missing after Tropical Depression Son Tinh triggered flash floods and landslides, submerging villages in the northern provinces of Thanh Hoa and Yen Bai, state-run Vietnam News Agency (VNA) reported Sunday.

Local government groups are "searching for missing ones, arranging temporary accommodation for households who have lost their homes, and actively evacuating and relocating people from dangerous areas," VNA said.

Residents clear debris in a village damaged by flash flooding in Vietnam's Yen Bai province on Saturday.

The government is also mobilizing forces to fix infrastructure, including homes, heath care centers, hospitals and schools.

Winds from the storm had reached up to 52 kph (32 mph) at 10 a.m. Sunday local time (11 p.m. Saturday ET). It is expected to continue to affect Vietnam until Tuesday, according to the Vietnam National Center for Hydro-Meteorological Forecasting.

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