A CH-46 Sea Knight transport helicopter with British and US soldiers on board has crashed in Kuwait, US defence officials said late Thursday.
"A marine helicopter has gone down in the area of operations," a Pentagon spokesman said, while US television reports claimed there were no survivors from the crew of 16.
The Sea Knight crash was the third incident involving US helicopters since hostilities began 24 hours ago.
An MH-53 Pave Low helicopter of the US Air Force special forces had a heavy landing during operations in southern Iraq. All six crew members survived unscathed.
Later Thursday, a US Army AH-64 Apache attack helicopter experienced similar problems landing in Kuwait. There were no casualties, according to a US official.
12 Britons, 4 Americans killed in US helicopter crash
Twelve British and four American soldiers on board a US CH-46 Sea Knight helicopter have been killed when it crashed in Kuwait, US military officials said late Thursday, revising their earlier casualty report.
Earlier in the day, the officials had said the dead soldiers included 12 Americans and four Britons.
Until now, the reason for the accident remains unknown, and an investigation is underway, said the officials.
The crash of the helicopter, assigned to the 1st Marine Expeditionary Force, occurred at 0037 GMT Friday morning in Kuwait,some 15 km away from the border with Iraq, they added.