In Chengdu, food prices rose because of the rainstorms.

At produce market near Shuhan Road, a kilogram of tomatoes sold for 9 yuan, four yuan more than normal, and blanched garlic went for 18 yuan, a 2 yuan hike.

"Fewer farmers have sent vegetables to the city because of the rainstorm," said vendor Xia Bi.

The Sichuan Provincial Meteorological Center has upgraded its orange rainstorm alert to red, as more rain is expected in Dujiangyan, Beichuan, Ya'an and Wenchuan over the next three days.

China has a four-tier color-coded warning system for severe weather, with red being the most serious, followed by orange, yellow and blue.

In neighboring Gansu province, three villagers remain missing after falling into floodwaters on Monday evening. Search and rescue efforts are underway, according to Xinhua News Agency.

Authorities in Gansu's Longnan issued a yellow alert for heavy rain early on Tuesday, as storms have been pounding the city since early on Monday. Local authorities also warned of the risk of potential geological disasters, Xinhua said.