18th anniv. of 9/11 attacks marked across U.S.

A staff member set flags during the Pepperdine Wave of Flags display at Pepperdine University in Malibu, the United States, on Sept. 11, 2019, to mourn the victims of the 9/11 terror attacks which happened 18 years ago. (Photo by Qian Weizhong/Xinhua)