Since July 18, wheat prices have increased for three straight days after Russia threatened to treat ships destined for Ukrainian ports as military targets.

Russia has been bombarding Ukrainian grain facilities in Odesa and other cities for the last three nights. Since the attacks began the evening of July 17, over 20 people have been injured , according to BBC News.

Adam Hodge, the Assistant U.S. Trade Representative for Media & Public Affairs, alleged that Russia had also planted more sea mines in the approaches to Ukrainian ports in an attempt to justify the country’s attacks on non-military ships.

The Kremlin did not immediately respond to a request for comment regarding the allegations.

Wheat prices grew by 8.2% on the European stock exchange from July 18 to July 19 to €253.75 (about $284) per ton. Meanwhile, U.S. wheat futures increased by 8.5%, representing the largest single-day jump for the commodity since just after Russia invaded Ukraine in February 2022.

The growing military action comes just days after Russia announced it would be pulling out of the Black Sea Grain Initiative on July 17. The agreement, which was created to limit global food shortages caused by Russia’s war in Ukraine, has allowed over 32 million metric tons of grain to be transported to the rest of the world since the conflict began in 2022.