Three people have died during a stampede at a Carrefour-owned supermarket in China, according to local reports.

The stampede, in which a further 30 were injured, happened in the city of Chongqing in south-west China, state media said.

A crowd waiting for hours to take advantage of a promotion on cooking oil caused the stampede after rushing through the doors when the store opened.

In the last year, cooking oil prices in China have soared; the supermarket in Chongqing was reportedly offering a 20% reduction in the price of rapeseed oil.