President Donald Trump on Tuesday lauded the men and women of United Flight 93 for saving countless lives. He called the field where the plane went down on Sept. 11, 2001 a monument to “American defiance.”

Trump said the nation shared the grief of family members whose loved ones were lost that day.

“We honor their sacrifice by pledging to never flinch in the face of evil ."

Commemorations also took place in New York and Washington.