The death toll had risen to 40 and 18 others remained missing as of 3 p.m. Saturday after hail and torrential rains battered a mountainous county in northwest China, authorities said late Saturday.

The storms had affected 358,000 people in Minxian county, Gansu province, forcing the evacuation of nearly 30,000 local residents. Another 87 people had been hospitalized.

Roads were blocked, houses collapsed, farmland destroyed, power supply and telecommunications service disrupted by the extreme weather, according to Xu Guangyao, director of the Minxian county civil affairs bureau.

A total of 950 tents, 1,270 beds and a great deal of relief supplies had been sent to the disaster-stricken area, but the local residents were still in need of relief supplies, he said. The stormy weather lasted just from 5 to 6 p.m. Thursday, but wreaked havoc in all of the county's 18 townships.

Minxian is a mountainous county in the city of Dingxi with a population of 450,000. It is located 150 km from Zhouqu county, where a rain-triggered mudslide killed more than 1,500 people in August 2010.