Washington — The Department of Justice is investigating suspicious trading timed to swings in the oil market, according to two sources familiar with the investigation. 

Reuters first reported the trading and the fact the U.S. Commodity Futures Trading Commission was investigating the trade. ABC News was the first to report of the Justice Department’s probe.

The oil market has been volatile amid the war with Iran. Tehran has effectively closed the strategic Strait of Hormuz to Gulf oil and gas exports, sending prices soaring and forcing nations to scramble for alternative supplies.

The average national price for a gallon of gas Wednesday was $4.51, according to AAA.