(Adds background) BAGHDAD, Feb 21 (Reuters) - The U.S. military said on Wednesday initial reports indicated that a Black Hawk helicopter with nine people on board had made a "hard landing" north of Baghdad. It was unclear why the helicopter made such a landing. U.S. military spokesman Major-General William Caldwell said another helicopter had picked up those on board. Insurgents have shot down seven helicopters in Iraq since Jan. 20, killing 28 people, mainly American soldiers. Five of those helicopters were U.S. military aircraft and two belonged to a private American security company. The high number lost has raised questions about whether insurgents are using new tactics, such as studying aircraft flight patterns, or have acquired sophisticated weaponry. U.S. commanders have said one reason they believe insurgents had focused on helicopters was to try to undermine a new security crackdown in Baghdad that formally began last week.
