The International Maritime Organization has documented 68 maritime incidents in the Strait of Hormuz following Iran’s blockade, with 19 sailors reported dead as of Friday. Iran began the blockade in late February, after which a series of incidents occurred in the strategically important waterway.

The IMO said the number of fatalities has risen in the incidents it has monitored since the blockade began. Its most recent listed incident occurred on August 17, when a projectile struck the engine room of the Liberia-flagged vessel Minoan Dignity, killing one sailor.

Maritime monitoring firm Windward identified the dead crew member as the ship’s chief engineer. The Strait of Hormuz is a major shipping route through which a significant amount of fuel for international trade is transported, and maritime security disruptions there have generated international concern.