Hundreds protested in Kunming, Yunnan province, but a march in Chengdu, Sichuan province, was prevented by police. The rallies were timed to coincide with the anniversary of the May 4 student demonstrations in Beijing in 1919.

Italy's largest oil firm might sell a 20 per cent stake in a gas block to CNPC to share the cost of developing the project, the people said, asking not to be identified because the talks are private.