The attack in Kirkuk, a disputed oil-rich city that has seen a recent rise in ethnic tensions, occurred while the capital remained relatively calm under a driving ban aimed at preventing such attacks during a major Shiite pilgrimage.
The U.S. helicopter was en route to support a planned mission when it made the forced landing in Youssifiyah, the military said, adding the cause was not immediately clear from initial ground reports but was being investigated. The two soldiers sustained non-life threatening injuries, according to the statement.
U.S.-led forces had secured the site and recovered the aircraft, military spokesman Lt. Col. Rudolph Burwell said.
An Iraqi army officer, who spoke on condition of anonymity because he wasn't authorized to release the information, said the helicopter went down after hitting an electricity pole at about 1:30 a.m. He said the raid was targeting a senior al Qaeda in Iraq leader in the agricultural area. Burwell said he could not confirm that report.
Youssifiyah, 10 miles south of Baghdad, is in the area known as the triangle of death for the insurgent activity there.
It was the second helicopter to go down in less than two weeks. On July 31, an AH-64 Apache helicopter went down after coming under fire in eastern Baghdad. The two crew members were safely evacuated, the military said.
Insurgents also shot down a U.S. military helicopter south of Baghdad on July 3, and the two pilots were rescued with minor injuries, the military said.
Scattered violence struck Iraqis elsewhere, with at least 15 people killed or found dead nationwide.
The deadliest attack struck the market in a predominantly Kurdish area in southern Kirkuk, 180 miles north of Baghdad. The suicide car bomber detonated his payload as the market was packed with midday shoppers buying vegetables and household goods.
Tensions have increased as Kurds seek to incorporate the oil-rich city into their autonomous zone in northern Iraq — a move opposed by Arabs and Turkomen in the area.
In other developments:
President Bush said he hoped al-Maliki's message to Tehran would be the same as the U.S. message — that Iran should halt the export of sophisticated explosive devices used to attack U.S. troops in Iraq or "there will be consequences."
The United States and Britain sought to expand the U.N. mandate in Iraq with a draft resolution facing a Security Council vote on Friday.
The sponsors had delayed the vote so that Iraq's prime minister could revise the text, which would authorize the world body to help the government promote national reconciliation, better relations with its neighbors, and deal with humanitarian concerns that have increased because of insecurity and fighting.
The newly revised text was circulated to the Security Council and Iraq's Foreign Minister Hoshyar Zebari sent a letter asking that the mandate of the U.N. mission, which expires Friday, be extended for a year — a requirement before the resolution can be adopted.