A drone strike damaged Ukraine’s grain infrastructure on the Danube River overnight, the latest in a raft of attacks on the country’s key crop-export channel. 

Russian drones hit grain elevators near the port of Izmail in the three-hour attack, and one worker from an agriculture company was killed, according to Odesa regional governor Oleh Kiper. Fifteen drones were shot down in the region, the city council said on Telegram. 

The Danube River has become Ukraine’s primary shipping route for agricultural goods since Russia exited the Black Sea grain deal in July, making it essential to clear this year’s better-than-expected harvest. 

Although the area has been repeatedly attacked in recent weeks, crop exports are still flowing. The Ukrainian Grain Association said last week that there are aims to increase volumes shipped via the river.

Wheat futures in Chicago traded little changed, holding near a three-month low. Large harvests in some other key producers, including major producer Russia, have tempered price gains.