The U.S. says it has expressed concern to the Chinese authorities . China says it is investigating what it describes as an `` isolated case '' About 50 protesters gathered around the car , some throwing objects . A spokesman for China's Foreign Ministry said in a statement that Beijing was "seriously concerned" about reports of violence and urged all sides "to exercise restraint and avoid any actions which could lead to further escalation
The U.S. says it has expressed concern to the Chinese authorities . China says it is investigating what it describes as an `` isolated case '' About 50 protesters gathered around the car , some throwing objects . The incident took place amid anti-Japanese protests in China .