At least 21 people have been killed by floods in Viet Nam's 4 central provinces in the past week and 8 are still missing, the government said on Sunday amid preparations for another tropical storm to hit the country.

A man paddles a boat near his submerged house during a flood in Viet Nam's Ha Tinh Province, October 15, 2016. Reuters

Fifteen of the victims were in Quang Binh Province, the region expected to be hit by typhoon Sarika by Wednesday, it said.

"We need to focus on searching for the missing," Deputy Prime Minister Trinh Dinh Dung told a meeting on preparations for the typhoon, according to a Viet Nam Television (VTV) broadcast.

Dung urged authorities in 22 coastal provinces to reinforce key infrastructure projects and prepare evacuation plans, and assured them the government would provide food relief in flooded areas.

State-run VTV warned viewers that many reservoirs were nearly full now and could burst at any time. It showed footage of people stranded on the roofs of their homes.

Around 500,000 people have been displaced and more than 100,000 houses submerged and damaged by floods, according to a government report.

According to the law of nature, the central region often experiences downpours and floods between September and November, due to the combined effect of a cold front and an intertropical convergence zone, being either a storm or a depression, Le Thanh Hai, deputy general director of the National Hydro-Meteorological Service elaborated.

The directions of typhoons Sarika and Haima are showed in this map. (Photo: Tuoi Tre)

Rainfall will not reach such a high amount if one of the components is missing, he added.

That there had been no typhoon in the region in the past two years was due to the influence of the El Nino phenomenon, Hai continued, adding that the country is now under the effect of the La Nina event.

As local citizens are still coping with the consequences caused by the flood, many central Vietnamese provinces are anticipated to be impacted by two new typhoons heading toward the East Viet Nam Sea, according to the expert.

Super storm Sarika, packing winds of up to 149kph, is likely to approach the country this week, causing a serious deluge in the central region and rain in the northern delta.

Another typhoon, Haima, which has formed east of the Philippines, could also enter the East Vietnam Sea within October, Hai said.

(Source: Tuoitrenews)