BEIJING, July 11 (Reuters) - Floods and landslides have killed at least 360 people across China this summer and destroyed more than 4 million hectares (15.4 million sq miles) of crops, Xinhua news agency said on Wednesday.

Direct economic losses were 24.3 billion yuan ($3.21 billion), according to latest figures from the State Flood Control and Drought Relief Headquarters.

"Apart from 217,000 houses wholly or partially destroyed, more than 4.28 million hectares of grain crops have been hit, with 2.03 million hectares totally destroyed," headquarters deputy director Cheng Dianlong was quoted as saying.

Most of the deaths occurred after downpours across the Jialing River Valley in the southwest province of Sichuan which have resulted in floods in almost all the tributaries of Jujiang River, a branch of the Jialing, and triggered severe mountain torrents, mud-rock flows and landslides.

"Ferocious floods battered 40 counties along their route, submerging the downtown areas of four counties and shattering two small dams," Xinhua said.

Cheng warned the situation across the Huai River Valley was at flashpoint with all trunk rivers there reporting dangerously high water levels.

China flooded dozens of evacuated villages to ease pressure from the swollen Huai in the eastern province of Anhui.

More rain was forecast for the next two days along the Huai, flowing through the central province of Henan and the eastern provinces of Anhui and Jiangsu.

A total of 545 people were killed by natural disasters in China in the first half of the year, according to a report released by the Ministry of Civil Affairs.

Another 78 people went missing as a result of natural disasters, including floods, landslides, mudflows, gales, snowstorms and earthquakes.