Insurgents launched a coordinated ambush against Iraqi soldiers northeast of Baghdad on Saturday, detonating a roadside bomb and then firing on the patrol, killing 19 and wounding two, officials said.
The attack took place near Adhaim, about 60 miles from Baghdad, Iraqi officials said. It came two days after a roadside bomb killed 10 U.S. Marines and wounded 11 others on a foot patrol near Fallujah in the deadliest attack against American forces in four months.
Elsewhere, a U.S. base at Mosul's airport came under mortar or rocket fire Saturday, wounding two American soldiers, the U.S. military said. Several detonations shook the installation — Forward Operating Base Courage — at about 6:50 a.m. the command said.
In Berlin, the German government said it was making intense efforts to secure the release of an aid worker and her driver kidnapped in Iraq on Nov. 25. In a video made public Tuesday, kidnappers threatened to kill Susanne Osthoff, 43, unless Germany stops dealing with the Iraqi government.
Foreign Minister Frank-Walter Steinmeier told reporters that "regrettably, we have not succeeded in the first week in establishing, indirect or directly, contact with the kidnappers."
Chancellor Angela Merkel has said Germany will not be "blackmailed" in the case.
Germany ardently opposed the U.S.-led invasion of Iraq and refused to send troops there. However, it has been training Iraqi soldiers and police outside the country.
The Al-Jazeera network broadcast a videotape and statement Friday in which the kidnappers of four Christian peace activists threatened to kill the hostages — two Canadians, an American and a Briton — unless all prisoners in U.S. and Iraqi detention centers were freed by Dec. 8.
Foreign Office Minister Douglas Alexander, interviewed by the British Broadcasting Corp., condemned the release of the latest hostage video.
"We are concerned about the welfare of the hostages and we deplore the release of these videos, not least because of the great distress to the family of (British hostage) Mr. (Norman) Kember and the other families involved, but our policy on this is well-established," he said.
A leading member of the British anti-war movement, Anas Altikriti, arrived Saturday in Iraq to try to win the release of the hostages.
The Christian activists — Kember, 74, of London; Tom Fox, 54, of Clear Brook, Va.; James Loney, 41, of Toronto; and Harmeet Singh Sooden, 32, of Canada — had been repeatedly warned by Iraqi and Western security officials that they were taking a grave risk by moving about Baghdad without bodyguards.
The activists were members of the Chicago-based Christian Peacemaker Teams. On Saturday, the group appealed to kidnappers to release their hostages.
"I would appeal to them and say that you are mistaken about who these four men are," group member Peggy Gish told The Associated Press in the Jordanian capital, Amman.
"They are really working for peace and justice. They are helping you and other Iraqi people."
The ambush against the U.S. Marines from Regimental Combat Team 8 occurred Thursday outside Fallujah, the former insurgent bastion overrun by U.S. forces in November 2004. All those who died were from 1st Marine Division, based at Twentynine Palms, Calif., the Defense Department said.
In Iraq, they attached to the unit based at Camp Lejeune, N.C. — a unit that has suffered some of the highest casualties of the Iraq war.
The U.S. command did not release many details of the attack, but a witness said it occurred at a mill in the village of Amiriyat al Fallujah, just outside the city. The bomb was fashioned out of four large artillery shells, U.S. officials said.
"More than 20 troops entered there and a huge explosion happened," said Mohsen Mohammed. "Afterward, the helicopters and tanks arrived in the area."
Later Saturday, Al-Jazeera broadcast an insurgent videotape showing a huge explosion targeting a U.S. foot patrol near Fallujah. Although the tape did not directly link the explosion to Thursday's attack, the Al-Jazeera announcer noted the Marine deaths as the tape aired.
The video from the Islamic Army of Iraq showed ground troops walking down a street on both sides of a Humvee when a huge fireball engulfed the scene, sending terrified Iraqi bystanders scrambling for their lives.
Al-Jazeera said the Islamic Army also claimed responsibility for a series of other attacks against U.S. forces north of Baghdad, in Nasiriyah and another in Fallujah.
In another video, also aired by Al-Jazeera, a group calling itself the Mujahedeen of Tal Afar claimed responsibility for destroying an American Bradley Fighting Vehicle in the northern city. The video showed that a bomb had exploded under the Bradley, but Al-Jazeera said it was not clear whether the footage was authentic.
The Marine unit's losses were among 14 new deaths in Iraq announced by the U.S. military Friday.
Three U.S. soldiers from the 48th Brigade Combat Team were killed in a traffic accident south of Baghdad, and the military said an Army soldier assigned to the 2nd Marine Division died of wounds suffered the previous day when his vehicle was struck by a rocket in Ramadi, 70 miles west of the capital.
Altogether, at least 2,124 have died since the war began, according to an Associated Press count.
The military statement said seven of the wounded Marines returned to duty, and the rest of the team was conducting "counterinsurgency operations throughout Fallujah and the surrounding area" to improve security for the Dec. 15 elections.
U.S. forces have stepped up military operations throughout the Sunni Arab regions west of Baghdad to cut off the flow of weapons, ammunition and foreign fighters entering the country from Syria and to reduce insurgent activity.
On Friday, the U.S. military launched a new offensive — Operation Shank — in Ramadi, capital of the insurgent-ridden Anbar province. About 200 Iraqi army soldiers and 300 U.S. Marines were taking part in the offensive, the fifth in Ramadi since Nov. 16.
U.S. officials hope the operations will enable Sunni Arabs to vote in the parliamentary elections without fear of insurgent reprisals, which the Americans blame in large part for the Sunni boycott of the January balloting.
Washington hopes a big Sunni turnout will produce a government that can win the trust of the Sunnis, the backbone of the insurgency, and convince more of them to lay down their arms. That would hasten the day U.S. troops could go home.
A major Sunni clerical group, the Association of Muslim Scholars, appealed to the Arab League and human rights organizations to intervene with the Americans to stop "the massacres in Anbar." The association is believed to have ties to some Sunni insurgent groups.
After months of silence, Iraq's top Shiite cleric is signaling to his followers that they should vote for the Shiite alliance in the upcoming election, aides said on condition of anonymity because they are not allowed to talk to the media.
Aides said Grand Ayatollah Ali al-Sistani is now telling people to vote for the Shiite alliance to "preserve Iraq's unity" and "protect Iraqis."