Beijing: Eight people were killed and four others reported missing in China as rainstorms wreaked havoc in southern areas as authorities on Saturday issued a blue alert for torrential rains in the next 24 hours, with more than 500,000 people affected in record downpour.

All casualties were reported in Xinyi, a small, county-level city in Maoming in Guangdong Province, the press office of the Communist Party of China Maoming said in a statement.

The rains have caused direct economic losses of 386 million yuan ($58.9 million, Dh58.9 million) so far, the city’s flood control and drought relief headquarters estimated.

Rescue teams were dispatched to relocate more than 2,800 people in dangerous areas, state-run Xinhua News Agency reported on Saturday.

The direct economic losses surpassed 1 billion yuan ($152.7 million). In the neighbouring Guangxi Zhuang autonomous region, rainstorms damaged roads, embankments and waterlocks, causing 100 million yuan of direct losses to water resources facilities alone.

Some parts of these provinces are going to see torrential rain of 100 to 130 millimetres within 24 hours.

From 80am on Saturday till Sunday, heavy rain and storms are expected in many southern provinces, including Guangdong, Hainan, Fujian and Yunnan provinces, the National Meteorological Centre (NMC) announced.

The meteorological authority on Saturday issued a blue alert, the lowest level in its four-tier warning system, for heavy rain in southern China in the next 24 hours. In China’s four-tier colour-coded weather warning system, red represents the most severe warning, followed by orange, yellow and blue.

Rainstorms caused flash floods and swollen rivers, leading to disrupted traffic and dislocation of residents in the city of Xinyi in south China’s Guangdong Province, which was one of the worst-hit areas in Friday’s rain, recording 465.5 millimetres of precipitation in 10 hours.

Of the 557,421 Maoming residents who suffered losses from the extreme weather, 542,000 were from Xinyi.

According to local authorities, 540,000 people have been affected by the strongest downpour in the city’s history, with 55,000 people forced to vacate after their homes were destroyed.

Flash floods and swollen rivers caused by the downpour trapped more than 1,000 middle school students in their classroom building in Pingzheng township of Beiliu City who were evacuated later on Friday.

The local government said the campus was flooded with water a metre deep after the local river burst its banks.

The rainstorms prompted evacuation of 7,444 people in Guangxi’s Yulin City, toppled 124 houses and seriously damaged another 25, the local government said.

The NMC cautioned that local governments should take emergency measures against storms, cut-off outdoor power supply in dangerous regions and prevent potential disasters, including mountain floods and landslides.