BEIJING — The death toll from torrential downpours that have ravaged southern China for the past week has reached 90, as rain continued to affect millions of people, authorities said Sunday. Floods and landslides triggered by the summer deluge have left a further 50 people missing and forced more than a million people living on river banks and in low-lying areas out of their homes, government agencies said. More heavy rain was expected as the cost of the disaster, which has hit great swathes of China's south, reached 11 billion yuan (1.6 billion dollars), according to the latest statement from the nation's civil affairs ministry. A total of 155,000 houses had been damaged -- almost half of which had collapsed -- and more than 500,000 hectares (1.2 million acres) of crops had been affected, the ministry said. Authorities have raised the level of their emergency response as rescue and flood-prevention work continues, it added.