美国警察枪杀黑人青年事件继续引发骚乱

Tensions are rising between police and residents in a suburb of St. Louis, Missouri, where an unarmed black teenager was shot and killed by a police officer. 

Police in riot gear fired tear gas and smoke bombs late Wednesday night at hundreds of residents who were protesting for a fourth consecutive night in the predominantly-black community Ferguson.

The community of 21,000 residents has been on edge since the death of 18-year-old Michael Brown last Saturday.  Ferguson police officials say Brown was killed after fighting with the policeman in his car.  But witnesses say the teenager was shot multiple times as he and a friend were walking from a store, and that his hands were raised to show he was surrendering. 

The demonstrations have turned violent, with some protesters vandalizing and looting stores.  Police officials have responded by deploying heavily-armed officers in military-style vehicles throughout the community, a sight that has worsened relations between residents and Ferguson's mostly white political leadership.