This undated photo shows roads and buildings inundated in Yongfu county after heavy downpours hit the Guangxi Zhuang autonomous region. (TANG SHAOJUAN / CHINADAILY.COM.CN)

The downpours that disturbed railway transportation and killed at least nine people in southern parts of the country are expected to continue and result in wide-ranging floods in the coming four days, authorities said.

Northeastern parts of Guangxi and central parts of Guangdong were forecast to be the worst affected with precipitation of 100 to 200 millimeters, the National Meteorological Center said

Nine people were killed and another five were missing in eight provincial regions, including Hunan and Guizhou provinces and the Guangxi Zhuang autonomous region, that were battered by heavy rainfall, according to the Ministry of Civil Affairs on Monday.

More than 1.7 million people were affected. 

Since June 1, many areas in southern parts of the country have received precipitation of 100 to 250 millimeters. The rainfall has resulted in floods in 52 rivers in the eight provincial regions, according to a media release from the Ministry of Emergency Management late on Sunday.

The National Meteorological Center said on Monday that precipitation in some areas in these regions reached 434 millimeters on Sunday.

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The center also renewed a yellow alert, the second lowest in the country's four-tier warning system, at 10 am on Sunday, saying that rainfall was expected to continue in these regions over a 24-hour period starting at 2 pm.

Northeastern parts of Guangxi and central parts of Guangdong were forecast to be the worst affected with precipitation of 100 to 200 millimeters, it said.

The rainfall has caused trouble in many areas.

Jianghua county in Hunan, for example, suffered the worst flood in 50 years on Saturday, which left one dead and four missing.

A preliminary calculation shows that the flood left 2,000 hectares of tobacco and over 460 hectares of rice inundated, the local authority said.

The torrential rain also caused a high-speed train to derail in Hezhou, Guangxi, on Sunday.

"It was frightening. It felt as if I was on a roller coaster," a passenger surnamed Chen told Chutian Metropolis Daily, a newspaper based in Hubei provincial capital Wuhan.

According to China Railway Nanning Group Co, the accident was caused by falling rocks brought down by rainfall.

The railway was cleared almost six hours after the accident occurred. No passenger was injured.

The rain was expected to continue for at least another four days, according to the National Climate Center.

As the rain band gradually moves northward, torrential rains will continue in parts of Hunan, Guizhou and Guangxi as they envelop the lower reaches of the Yangtze River. Flooding will occur in 16 water bodies in affected regions, it said.

It also said the county will experience a longer Plum Rains season－a long period of continuous rainy or cloudy weather that usually occurs during June and July as plums ripen－with even more precipitation this year.

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While the region south of the Yangtze entered the season on June 1, a week earlier than normal years, the season was expected to begin in the middle and lower reaches of the Yangtze on Monday, six days ahead of its normal time, it said.

The flood control situation in affected regions has become "not optimistic" as water continues to accumulate because of the persistent rainfall, said Ye Jianchun, secretary-general of the State Flood Control and Drought Relief Headquarters.

Reservoirs should discharge water in advance so that they could help store floodwaters to reduce damage, and local authorities should enhance patrols to remove safety hazards, said Ye, also vice-minister of Water Resources.