China evacuated thousands more people and broke a dyke to release floodwater on Wednesday as several southern regions fought to control some of the worst floods for decades.

Relief workers evacuated more than 10,000 people from villages in the south—eastern province of Jiangxi early Wednesday after flash floods and the overflow of three reservoirs in Poyang county, state media said.

The workers were rushing to widen emergency channels to divert some of the water away from villages, the government’s Xinhua news agency quoted officials as saying.

The Jiangxi meteorological department issued a red alert for floods early Wednesday, warning of more torrential rain, the agency said.

In neighbouring Anhui province, troops used explosives on Wednesday to blast holes in four dykes along the Nitanggou river to reduce the risk of flooding to a city of 100,000 people.

The water let out from a reservoir on the river would swamp 400 hectares of farmland that was “sacrificed” to safeguard people in Anhui’s Shipai township, Liu Feiyue, a local government official, told the agency.

“Shipai township is densely populated. If the dyke bursts, the consequences would be disastrous,” Mr. Liu said.

About 1,000 people living close to the river were evacuated, he said.

In the three adjoining provinces of Yunnan, Sichuan and Hunan, at least 37 people died and 37 were missing after several flash floods and landslides on Tuesday, reports said.

Torrential rain has caused floods and landslides in many parts of southern China over the past three months.

At least 500 people have died, including more than 100 in the past week, and hundreds of thousands of people have lost their homes either temporarily or permanently.

Typhoon Conson was also expected to bring more rain after it makes landfall in the southern province of Guangdong on Thursday or Friday.

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