From the New York Times:

After three nights of increasingly heavy rioting, the police were taking no chances on Monday, deploying dozens of busloads of officers before dusk and blocking eve

Protesters, who say the pharmaceuticals factory at Xinchang pollutes their water, were blocked on Monday by police barricades. There is rising discontent in China with the authorities’ failure to respond to grievances.

But the angry residents in this village 180 miles south of Shanghai had learned their lessons, too, they said, having studied reports of riots in towns near and far that have swept rural China in recent months. Sneaking over mountain paths and wading through rice paddies, they made their way to a pharmaceuticals plant, they said, determined to pursue a showdown over the environmental threat they say it poses.