Floods caused by heavy rains have killed 28 people in China in four days and left another 16 missing, the Ministry of Civil Affairs said on Monday.From late Thursday till Monday night, the rains forced 504,000 people to relocate in many provinces including Anhui, Guizhou, Hubei, Hunan, Jiangxi, Sichuan, Yunnan and Zhejiang, Xinhua news agency reported. Nearly 6,500 houses collapsed and 60,000 were damaged. About 468,800 hectares of farmland was flooded and 45,200 hectares of crops were destroyed.Direct economic losses were estimated at 9.46 billion yuan ($1.38 billion).