WASHINGTON (AP) — A senior U.S. defense official is confirming that a top Islamic State military commander was killed by a coalition airstrike in Syria on Monday.

The official says that Abu Jandal al-Kuwaiti was killed near Tabqa Dam. He was a key leader of the group in Raqqa. No other details were available.

The Britain-based Syrian Observatory for Human Rights said earlier this week that he had been targeted by U.S.-led coalition aircraft. And IS supporters on social media had indicated on Tuesday that he had been killed.

The U.S. confirmation was the first official coalition acknowledgement of his death.

The U.S.-backed Syrian Democratic Forces have been battling Islamic State fighters near the strategically located dam, aided by a barrage of coalition airstrikes in the region.