BAGHDAD, Iraq -- A Marine helicopter made a hard landing Monday in a remote desert area of Anbar province, injuring 18 people -- the third U.S. aircraft to go down in the insurgent stronghold in two weeks. The military also announced that three American soldiers were killed in a roadside bombing north of the capital Sunday, putting December on track to be one of the deadliest months of the war.
The latest casualties underscored a major danger for Americans in Iraq, where the military relies heavily on air travel to transport troops and ferry officials and journalists to remote locations and to avoid the dangers of roadside bombs planted by insurgents.
The announcements came on a day that saw at least 66 more people killed or found dead in the Baghdad area and northern Iraq. They included 46 men who were bound, blindfolded and shot to death in Baghdad -- the latest apparent victims of sectarian death squads.
The CH-53E Super Stallion, the U.S. military's largest helicopter, was conducting a routine passenger and cargo flight with 21 people on board when it went down about noon, the U.S. command said, adding that hostile fire did not appear to be the cause.
Nine of the 18 injured were treated and returned to duty, it said. The military did not give the exact location where the hard landing occurred, saying recovery efforts were under way.
On Dec. 3, a Sea Knight helicopter carrying 16 U.S. troops went down in a lake, killing four. On Nov. 27, a U.S. Air Force fighter jet crashed in a field, killing the pilot. Both took place in Anbar, a volatile Sunni-dominated province the size of North Carolina.
Sunday's roadside bombing that killed the three soldiers took place while they were on a late-night patrol north of Baghdad, the military said. Two soldiers were wounded.
The attack raised to 46 the number of American troops who have died this month, an average of 4.6 a day. By comparison, an average of 3.4 were killed each day in October, the fourth-deadliest month of the Iraq war with 105 deaths.
At least 2,934 members of the U.S. military have died since the U.S.-led invasion in March 2003, according to an Associated Press count.
Last week, the bipartisan Iraq Study Group concluded the U.S. could be out of Iraq by early 2008 if it dramatically increased the number of troops advising Iraqi units and threatened to cut off aid to the Iraqi government unless it met certain milestones. Bush administration officials are weighing the panel's recommendations as well as other options, including a short-term buildup of U.S. troops in Iraq.
On Monday, Iraq's government struck back at criticism that it has failed to protect Iraqis from the rampant sectarian violence in their country.
Defense Ministry spokesman Mohammed al-Askari defended army efforts to prevent violence between Shiites and Sunnis in Baghdad, saying government security forces are doing all they can to keep people from being killed or driven from their homes in neighborhoods with mixed populations of both Muslim sects.
He said one example occurred Monday, when Iraqi soldiers rushed to Ghazaliyah, a primarily Sunni area of west Baghdad, to free 23 Iraqis right after they were taken hostage at a checkpoint set up by suspected Shiite militiamen.
"We killed one terrorist and arrested four others," al-Askari said.
A recent outbreak of attacks against Sunnis in Hurriyah, a mixed neighborhood of northwestern Baghdad, has sparked apparent retaliatory violence from the minority sect and raised new fears of an organized campaign by Shiite militants to drive Sunnis from the area and strengthen militia control of the capital's north.
Witnesses say scores of Sunni families have been fleeing Hurriyah in recent weeks, and Sunni organizations claim that the Shiite-dominated Iraqi army and police have done little to stop the violence.
Al-Askari said five Iraqi army companies -- which would be about 600 soldiers -- are stationed in Hurriyah to protect all its residents.
"Some people are using places such as Hurriyah to support their false claim that the government and its security forces are incapable or unwilling to stop such violence," he said.
The neighborhood was calm Monday, with shopkeepers reopening and students returning to school, according to a police officer, Rahman Abdel-Hussein.
"We can't deny the presence of the outlaws in Hurriyah who have managed to intimidate residents and force some of them out of their houses. But Hurriyah isn't the only area where this is happening in Baghdad. It's going on in other neighborhoods, too, and all Iraqis are being targeted, not only one sect," al-Askari said.
Amid concerns the violence could have regional implications, more than 30 prominent Islamic clerics from Saudi Arabia called on Sunnis around the Middle East to support their brethren in Iraq against Shiites and praised the insurgency.
Saudi Arabia, like most Arab countries, is predominantly Sunni but has a significant Shiite minority. Saudi Arabia, Jordan and Egypt have all expressed concerns over increasing Shiite power in Iraq and other parts of the region, which they see as an opening for Iranian influence.