The United States has launched an investigation to determine how the terror group ISIS was able to acquire a large number of Toyota pickup trucks and SUVs ABC News reported this week.

Japanese car manufacturer Toyota, the world’s second-largest auto maker, has pledged full cooperation with U.S. authorities and is “supporting” the inquiry led by the Terror Financing division of the U.S. Department of the Treasury. According to Toyota sales data, the number of Hilux and Land Cruisers sold tripled from 6,000 in Iraq in 2011 to 18,000 sold in 2013. However, sales dropped to 13,000 in 2014.