Americans marched in star-spangled parades and gathered for fireworks shows as they celebrated Independence Day in traditional style.
The Department of Homeland Security and the Federal Bureau of Investigation issued an alert last week asking local authorities and the public to remain vigilant for possible threats following recent calls for violence by leaders of radical Islamist group Islamic State.
In New York City, the nation’s biggest police force assigned about 7,000 officers and nearly all its counterterrorism personnel to handle security around Independence Day events.
On the U.S. West Coast, which is battling wildfires, communities in Washington state and Oregon restricted or banned fireworks for fear of more blazes. Cupertino, California, and Anchorage, Alaska’s largest city, also canceled firework shows.