Four arrests have been made in the terror attack in Spain that left 14 people dead and more than 100 injured.

ISIS has since claimed responsibility for the attack. Three of the terror suspects are Moroccan, and one is from Spain. None of the suspects are said to have previous terror backgrounds.

According to the State Department, at least one American was killed and another injured in the attacks.

The department did not identify either of the Americans, but said the injured person suffered only a minor wound.

Police are still looking for the driver of the van who plowed through the crowded street.

Police in Span were able to stop another attack shortly after the Barcelona attack in the resort town of Cambrils, which is south of Barcelona, after a car plowed down and injured six people near a boardwalk. Police say they shot and killed five suspects carrying fake bomb belts. 

According to police, the attack is related to both the van attack in Barcelona and a house explosion on Wednesday in another town.