International Desk:
Nearly 40 people have died in Vietnam and Cambodia and scores more are missing, including rescuers, due to prolonged heavy rain and flash flooding as tropical storm Nangka edges towards the Vietnamese coast.

Heavy rains since early October have caused deadly floods and landslides in several provinces in central Vietnam and displaced thousands of people in western Cambodia, officials and state media said.

The floods are expected to worsen in the coming days, with tropical storm Nangka forecast to dump more rain as it makes landfall in Vietnam on Wednesday.

Nangka, packing wind speeds of up to 100km/h will trigger heavy rain of up to 400mm in parts of northern and central Vietnam from Wednesday through Friday, its weather agency said.

Ongoing flooding has killed at least 28 people in Vietnam and 11 in Cambodia, where almost 25,000 houses and 84,000 hectares of crops have been damaged, according to local media.

Vietnamese disaster management authorities said more than 130,000 houses had been affected.

Seventeen construction workers were missing following a landslide at the site of a hydropower dam project in the central Vietnamese province of Thua Thien Hue, state media reported.

An additional 13 people sent to rescue the workers are also missing, the state-run Nhan Dan newspaper reported on Tuesday.

Vietnam's Prime Minister, Nguyen Xuan Phuc, instructed the defense ministry to send more rescue troops to the site of the landslide, according to a government statement. ‍Source: Australian Associated Press