BAGHDAD Five U.S. service personnel were killed when a military transport helicopter crashed during a routine flight west of Baghdad on Tuesday.
The crash takes the death toll for the U.S. military to 10 in the past two days.
The U.S. military said the CH-47 Chinook helicopter crashed near its al-Taqaddum air base outside Falluja, 50 km (30 miles) west of Baghdad, while conducting a "routine post-maintenance check flight".
There was no indication whether it was shot down. An investigation is under way.
The deaths of the five on board the helicopter takes the total number of U.S. military personnel killed in Iraq since the 2003 invasion to topple Saddam Hussein to at least 3,699.
So far in August at least 41 U.S. service members have died, compared with a total of 71 for July.
The military said earlier three soldiers were killed in an explosion in northern Nineveh province on Monday and another soldier died in combat in Baghdad the same day.
Another soldier was killed in combat on Tuesday.
At least 11 helicopters have been shot down since the start of the war, killing 35 service members. In the worst incident this year, 12 military personnel died when a Black Hawk helicopter was shot down on January 20.
Seventeen soldiers were killed when two Black Hawks collided under fire in northern Mosul on November 15, 2003, 13 days after a Chinook was shot down near the same air base in Falluja, killing 16 U.S. troops on board.