BAGHDAD, April 18 (Xinhua) -- A U.S. soldier was killed and three others injured in a helicopter crash in Salahudin province in north of Baghdad, the U.S. military said on Sunday.
A U.S. military statement said that the accident, which took place late on Saturday, was not attributed to hostile fire.
An investigation is underway, it said.
The name of the deceased is being withheld pending notification of next of kin, it added.
The latest death brings the number of U.S. soldiers who have been killed in Iraq to about 4,391, since the breakout of the U.S.- led war on Iraq in 2003, according to media account based on Pentagon figures.