All seven service members aboard a US helicopter that crashed in Iraq were killed, the Pentagon has said.
US officials said seven people were on board when the aircraft crashed in western Iraq on Thursday.
The crash did not appear to be the result of enemy activity and is under investigation, the Pentagon said.
US Army Brigadier General Jonathan P Braga, director of operations in the fight against Islamic State in Iraq and Syria, said: "This tragedy reminds us of the risks our men and women face every day in service of our nations. We are thinking of the loved ones of these service members today."
The helicopter was used by the US Air Force for combat search and rescue, and went down near the town of Qaim in Anbar province.
The Pentagon said an accompanying US helicopter immediately reported the crash and a quick-reaction force comprised of Iraqi security forces and coalition members secured the scene.
The names of those killed will be released after next of kin have been notified, the statement added.
The US-led coalition battling IS has an outpost in Qaim, which is near the Syrian border.
The anti-IS campaign accelerated through much of last year as coalition and Iraqi forces battled to take back a string of cities and towns.
Prime minister Haider al-Abadi declared victory over IS in Mosul in July.
In the following months, Iraqi forces retook a handful of other IS-held towns including Tal Afar in August, Hawija in September and Qaim in October.
In November, Iraqi forces retook the last Iraq town held by IS - Rawah, near the border with Syria.
The US-led coalition has continued to work with Iraq and Syrian Democratic Forces to shore up the border region to make sure foreign fighters and insurgents cannot move freely across the region.