A United States military aerial refueling aircraft has crashed in western Iraq, killing four crew members, according to a statement released by the United States Central Command (CENTCOM).
The aircraft, a Boeing KC-135 Stratotanker operated by the United States Air Force, went down during an incident involving two aircraft.
CENTCOM confirmed that four of the six personnel aboard the aircraft were killed, while rescue efforts for the remaining crew members were ongoing.
“Four of six crew members on board the aircraft have been confirmed deceased as rescue efforts continue,” CENTCOM said in a statement posted on X.
The command added that preliminary findings indicate the crash was not the result of enemy action.
“The loss of the aircraft was not due to hostile fire or friendly fire,” the statement said, noting that an investigation into the incident is currently underway.
A second aircraft involved in the incident landed safely, the military said.
Earlier, Iran’s military claimed the aircraft had been shot down by a missile launched by an allied militia group in Iraq.
Iranian state television carried a statement alleging that the plane had been downed by a member of the Islamic Resistance in Iraq, a coalition of Iran-aligned armed factions operating in the country.
The group also claimed responsibility for targeting another aircraft that it said managed to escape the attack.
Since the outbreak of the war between the United States and Iran last month, the alliance has frequently claimed attacks on US military interests across Iraq and other parts of the Middle East, although it rarely provides details about specific targets.
The crash marks at least the fourth US military aircraft lost since the conflict began.
Earlier in the war, three McDonnell Douglas F-15E Strike Eagle fighter jets were mistakenly shot down by Kuwaiti forces over Kuwait during intense combat operations. All six crew members aboard those aircraft successfully ejected, according to CENTCOM.
At the time, the military said the incident occurred amid ongoing combat operations that included attacks by Iranian aircraft, ballistic missiles and drones.
The KC-135 Stratotanker, which has been in service for more than six decades, is primarily used to refuel military aircraft mid-air. It typically operates with a three-member crew consisting of a pilot, co-pilot and boom operator, although some missions also require a navigator.
The aircraft is also capable of carrying up to 37 passengers, according to a US Air Force factsheet.
The latest loss comes as the financial cost of the war continues to mount.
According to a report by The New York Times, US lawmakers were told during a Pentagon briefing that the first week of the conflict cost more than $11.3 billion.
The figure reportedly excludes several expenses related to the military buildup prior to the strikes, suggesting the total cost could rise significantly.
Defense officials had earlier informed Congress that approximately $5.6 billion worth of munitions were used in the first two days of fighting alone — a rate of expenditure far higher than earlier public estimates.
Meanwhile, analysts at the Center for Strategic and International Studies estimated that the first 100 hours of the US military campaign, known as Operation Epic Fury, cost about $3.7 billion — equivalent to more than $891 million per day.
With the deaths from the crash, the number of US service members killed in the ongoing conflict with Iran has risen to at least 11.
