<p>Thousands of people marched through a Hong Kong border town on Sunday to oppose traders from mainland China.</p>.<p>They rallied in Sheung Shui, which lies across the border from the mainland city of Shenzhen.</p>.<p>For years, traders have bought goods from the district to sell at a markup in Shenzhen.</p>.<p>The practice is called “parallel trading" because it happens in a grey area alongside legal trade.</p>.<p>Some black-clad protesters held up signs that read “SARS,” an apparent reference to a mysterious infectious disease that may have been brought to Hong Kong from the central Chinese city of Wuhan, where at least 44 people have been infected.</p>.<p>The outbreak has revived memories of the 2002-2003 SARS epidemic that began in southern China and killed more than 700 people.</p>.<p>Police used tear gas on demonstrators who hurled petrol bombs at the Sheung Shui police station, authorities said.</p>.<p>While the procession ended at 2:50 pm, some demonstrators refused to disperse and remained in standoffs with riot police.</p>.<p>About 100 protesters marched through a Sheung Shui mall last month, demanding that mainland Chinese traders leave the territory.</p>.<p>Hong Kong, a semi-autonomous Chinese territory, has seen more than six months of anti-government demonstrations. (</p>
<p>Thousands of people marched through a Hong Kong border town on Sunday to oppose traders from mainland China.</p>.<p>They rallied in Sheung Shui, which lies across the border from the mainland city of Shenzhen.</p>.<p>For years, traders have bought goods from the district to sell at a markup in Shenzhen.</p>.<p>The practice is called “parallel trading" because it happens in a grey area alongside legal trade.</p>.<p>Some black-clad protesters held up signs that read “SARS,” an apparent reference to a mysterious infectious disease that may have been brought to Hong Kong from the central Chinese city of Wuhan, where at least 44 people have been infected.</p>.<p>The outbreak has revived memories of the 2002-2003 SARS epidemic that began in southern China and killed more than 700 people.</p>.<p>Police used tear gas on demonstrators who hurled petrol bombs at the Sheung Shui police station, authorities said.</p>.<p>While the procession ended at 2:50 pm, some demonstrators refused to disperse and remained in standoffs with riot police.</p>.<p>About 100 protesters marched through a Sheung Shui mall last month, demanding that mainland Chinese traders leave the territory.</p>.<p>Hong Kong, a semi-autonomous Chinese territory, has seen more than six months of anti-government demonstrations. (</p>