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Input: ISIS is on the run in Iraq and Syria  but  acting Secretary of Homeland Security Elaine Duke  said radical Islamic terrorists are plotting a new 9/11-scale attack.
In a speech at the U.S. embassy in London   Duke  said smaller  low-level attacks that include the use of everyday objects like knives and vehicles were designed to maintain their support while working on bigger attack targets  U.K.-based news outlets reported.
Referring to strikes in which terrorists have attacked people using knives or vehicles   Duke  said "Creating terror is their goal."
 Duke  warned it was taking less time for terrorists to plan attacks as they could exploit "safe spaces online" to evade detection  the outlet noted.
 She  added one of the biggest threats to the safety of aviation travel was the free movement of goods and people between countries.
"What we believe is that because of the movement of goods and people  we have to raise the baseline worldwide  we can't only consider our borders "  she  said.

Acting DHS Secretary Elaine Duke: Threat of 9/11