CHENGDU -- Five people were killed and two others badly injured on Wednesday when a mud-rock flow struck a village in southwest China's Sichuan Province, officials said.

The early morning mud-rock flow, triggered by heavy rain, destroyed the houses of seven families, the walls of a primary school and several hectares of farmland, said officials with the Sichuan provincial headquarters of disaster relief.

Traffic was interrupted on the local highway after mud and rock spewed across it.

Injured people were sent to hospital. Officials from Ningnan county government hurried to the site.

Officials from the provincial government left Chengdu, capital of Sichuan, for Dahuadi village on Wednesday morning to help with disaster relief work.

However, showers and thunderstorms are forecast for Wednesday evening, making disaster relief work difficult.

The economic loss is yet to be estimated.