U.S. intelligence and law enforcement authorities share a growing concern of an ISIS-inspired attack in the country through the July 4 weekend, sources told NBC News.
The threat "is based on both intelligence and analysis," the intelligence and law enforcement sources said, declining to go into detail.
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The analysis of the threat is based in part on the "new normal" of ISIS planning, which uses social media to encourage followers worldwide to attack on both small and large scales.
Information regarding the Fourth of July threat came before Friday's terror attacks in France, Tunisia and Kuwait, the intelligence and law enforcement officials said.