CHANGSHA -- A dike in a county in Central China's Hunan province breached around 11 am Sunday, one hour after local authorities began the urgent evacuation of residents.

Residents were being transferred when the breach happened at a flood detention basin called Xinhua by local residents in Huarong county, according to an official with Hunan Provincial Flood Control and Drought Relief Headquarters.

Judging from the current water level, substantial casualties are not expected, said the official.

The Xinhua flood detention basin covers 4,400 hectares and is home to over 27,000 people.