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

People mourn the victims of the 9/11 terrorist attacks at the National September 11 Memorial and Museum in New York, the United States, Sept. 11, 2019. People paid their tributes here on Wednesday to mourn the victims of the 9/11 terrorist attacks which happened 18 years ago and claimed thousands of lives. (Xinhua/Li Rui)