BAGHDAD -- Militants killed five US Marines and authorities found 21 bodies near the Syrian border, where American and Iraqi troops conducted two recent major operations aimed at crushing a tenacious insurgency, US and Iraqi officials said yesterday.
The Marines, from the Second Marine Expeditionary Force, were killed by a roadside bomb Thursday during combat operations near the Sunni town of Haqlaniyah, 90 miles north of Baghdad, the military said. The site is part of volatile Anbar Province, an insurgent stronghold.
The deaths were the most in a single incident for US forces since the makeup of the new Iraqi government was announced April 28. They brought to 37 the number of Americans killed since that date, including nine since Tuesday.
Meanwhile, the US military said yesterday that it has launched a criminal inquiry into the killings of two Army officers at a base in Tikrit. Captain Phillip T. Esposito and First Lieutenant Louis E. Allen of the Second Infantry Division, New York Army National Guard, were killed Tuesday evening.
Military investigators initially thought the deaths were caused by enemy artillery or mortar rounds from a location some distance away. ''Upon further examination of the scene by explosive-ordnance personnel, it was determined the blast pattern was inconsistent with a mortar attack," the statement added without elaborating.
The 21 Iraqi bodies discovered near the Syrian border were thought to be those of missing soldiers. They were shot repeatedly in the head and found blindfolded, with their hands tied behind their backs. Three were beheaded.
Twelve victims were found near a small hamlet called Jabab, in Anbar province about 19 miles east of Qaim. The other nine bodies were found near Qaim.
The killings were a clear sign of the profound difficulties faced by US and Iraqi forces in Anbar province around the dusty, lawless town of Qaim, and their inability to seal the desert border with Syria despite major efforts to boost their presence in the area.
The bloodshed came as politicians seeking a negotiated solution to the insurgency once again wrangled over a promise to give Sunni Arabs a greater say in charting Iraq's future.
Iraqi politicians are divided over President Jalal Talabani's promise to give Sunni Arabs more seats on a 55-member committee drafting Iraq's first postwar constitution. The charter must be ready to present to the 275-seat National Assembly by mid-August and will go before Iraq's voters in a referendum two months later.
US military intelligence officials believe the Qaim area is at the crossroads of a major route used by groups such as Al Qaeda in Iraq, led by Abu Musab al- Zarqawi, to smuggle foreign fighters into the country.
''It's like the Mexican-American border there. There are attempts being made to seal it," said a senior US military intelligence official.
The bodies were thought to be those of off-duty Iraqi soldiers who left their base near Qaim two days earlier in civilian clothes aboard two minivans, headed to Baghdad for a vacation.
Marines carried out two major operations in the area last month, killing 125 insurgents in the first campaign, Operation Matador, and 14 in the second, Operation New Market. Eleven Marines were killed in the actions, designed to scatter and eradicate insurgents using the road from Damascus to Baghdad.
Insurgents are so rooted in the region that after a May 29 gun battle in a village between Qaim and Haqlaniyah, US forces found the body of the kidnapped governor of Anbar Province chained to a propane tank and killed by falling rubble.
As part of its effort to increase its presence, the Iraqi Army boosted the number of soldiers at the frontier post of Akashat, near Qaim, from about 100 before Operation Matador to nearly 750 now. Akashat is where the missing soldiers were based.
In other developments yesterday:
The US military also announced that a US soldier died Thursday of noncombat injuries near Tuz Khormato, about 130 miles north of Baghdad.
A car bomb killed four men and wounded nine as they sat outside a restaurant in Baghdad waiting to pick up sandwiches.
Al Qaeda in Iraq claimed in an Internet posting that it abducted 36 Iraqi soldiers in western Iraq on Wednesday, and threatened to kill them unless the government released ''Muslim women" from prison.
Gunmen killed the dean of the police academy in the southern city of Basra.