At least 21 people have been killed and six are missing after a flash flood and landslides triggered by heavy rain struck Weiziping village in the outskirts of Xi'an, capital of Shaanxi province in Northwest China, according to the city's bureau of emergency management on Sunday.

The disasters struck Weiziping in the Chang'an district shortly after 6 pm on Friday. The village is located on the northern slope of the Qinling Mountains.

Two residential houses in the village were destroyed, and roads, bridges, power supply equipment and other infrastructure were damaged.

A local restaurant owner said it was dinnertime when the torrential rain hit, and some tourists were swept away by the sudden flood.

A woman surnamed Wu, who runs a homestay business in the village, told reporters that she has not received any information from her family about their safety, and she is still waiting for updates from rescue personnel.

Emergency records show that the Xi'an meteorological center issued an orange alert, the second highest in China's four-tier color-coded warning system for rainstorms, at 12:35 pm on Friday, and upgraded the alert to the highest level three hours later.

A team of more than 100 rescue personnel that arrived at the site on Friday night had relocated 81 people and searched 65 kilometers of river bank by Sunday morning, according to news reports.

By Sunday afternoon, the authorities had dispatched nearly 1,000 rescuers to the village and relocated 186 people. Most of the damaged infrastructure, including electricity and telecommunications, has been repaired and reopened for service, according to the city's emergency authorities.

The province's Party Secretary Zhao Yide and Governor Zhao Gang arrived at Weiziping on Saturday to lead rescue and disaster relief efforts.