Tillerson re-pledges to 'eliminate' terror threat

Tillerson spoke as he welcomed Belgium's Foreign Minister Didier Reynders to the State Department, and officials confirmed that a Belgian woman was among those killed in the assault.

"Once again we've seen the evil face of terror in our own borders, but this is a face that knows no borders," Washington's top diplomat told reporters.

"We welcome and appreciate the strong coalition of all partners in this fight against terrorism globally and we will continue that fight until we can eliminate this threat to all American citizens and all our friends and allies," he vowed.

Tillerson pledged "complete solidarity" with Argentina, which lost five citizens when the attacker ploughed into a bike lane in a pickup, and Belgium, which had one dead and several injured.

Reynders thanked US authorities for their efforts to save and treat the Belgian victims.

"We will continue to fight together against the terrorism," he said. "We need also to exchange the best practices to fight against radicalization, homegrown terrorism."

Police shot the 29-year-old suspect, Sayfullo Saipov, in the abdomen after he crashed into a school bus Tuesday and exited his pickup truck, brandishing paintball and pellet guns.

He remains in custody and is expected to survive.

Saipov has been identified as an immigrant from Uzbekistan. Officials say he became radicalized after moving to the United States and left a note "a note that referenced ISIS."