Elsewhere Tuesday, a mortar attack killed at least four Iraqi National Guard soldiers and wounded 80 at a base north of Baghdad. An American contractor also died when mortar shells crashed onto a U.S. base in the Iraqi capital. And three car bombs exploded in the northern city of Mosul, killing two Iraqi civilians and wounding three.
Margaret Hassan, who holds British, Irish and Iraqi citizenships and is married to an Iraqi, is among the most widely known humanitarian officials in the Middle East. She is also the most high-profile figure to fall victim to a wave of kidnappings sweeping Iraq in recent months.
The Arab television station Al-Jazeera broadcast a brief video showing Hassan, wearing a white blouse and appearing tense, sitting in a room with bare white walls. An editor at the station, based in Qatar, said the tape contained no audio. It did not identify what group was holding her and contained no demand for her release.
In other developments:
Hassan, who is in her early 60s, was kidnapped about 7:30 a.m. while being driven from her home to CARE's office in a western neighborhood of the capital, a CARE employee said. The employee said the group did not employ armed guards.
In an interview with Al-Jazeera, Hassan's husband, Tahseen Ali Hassan, said his wife was abducted near the CARE office.
"Two cars intercepted her from the front and back," he said. "They attacked the car and pulled out the driver and a companion. Then they took the car to an unknown destination."
He said his wife had not received threats and that the kidnappers had not contacted anyone with any demands. "Nothing like this happened before, because CARE is a humanitarian organization, and she has served the Iraqi people for 30 years," he said.
Hassan has lived in Baghdad for 30 years, helping supply medicines and other humanitarian aid and speaking out about Iraqis' suffering under international sanctions during the 1990s.
She went to work for CARE International soon after it began operations in Iraq in 1991 following the Gulf War, with programs focusing on rebuilding and maintaining water and sanitation systems, hospitals and clinics.
The kidnapping was the latest attack against humanitarian organizations, many of which have curtailed operations and withdrawn international staff because of the violence in Iraq. It also follows a wave of abductions targeting foreigners in the heart of the capital.
Although militants have kidnapped at least seven other women over the past six months, all were later released. By contrast, at least 30 male hostages have been killed, including three Americans beheaded by their captors. Hassan's abduction occurred less than two weeks after a video posted on an Islamic Web site showed the beheading of British hostage Kenneth Bigley.
CARE said Hassan was born in Britain, but the British and Irish foreign offices said she was born in Ireland, which is not part of the U.S.-led coalition in Iraq. When the kidnappers sent the tape to Al-Jazeera, they said they had abducted a "British aid worker," according to the station.
The British government is weighing a U.S. request to shift some of the country's 9,000 soldiers from relatively peaceful southern Iraq to areas south of Baghdad — presumably to free U.S. troops for an all-out assault on the insurgent bastion Fallujah.
British lawmakers are worried about sending their soldiers to the more volatile U.S.-controlled sector at a time when public opposition to the war in Britain has reduced Prime Minister Tony Blair's popularity.
The U.S. command said U.S. Marines and Iraqi soldiers have rounded up nearly 130 suspected insurgents over the past two days in areas south of Baghdad where British media say the British forces would be sent.
U.S. officials have admitted in the past that faulty intelligence had led to the arrests of thousands of Iraqis who had no ties to the insurgency. However, officials claim their intelligence is better now that Iraqi security forces are playing important roles in such operations.
The mortar attack on the Iraqi National Guard occurred early Tuesday when six mortar shells crashed onto a base in Mushahidah, 25 miles north of Baghdad. The troops were lined up in a courtyard for the morning formation, according to Iraqi and multinational officials.
The U.S. military said four guardsmen were killed and 80 wounded. Iraqi officials on the scene said five guardsmen were killed and more than 100 injured. American helicopters helped ferry the wounded to U.S. hospitals in the area. Iraqi police and security units have been a frequent target of insurgents trying to undermine U.S.-led security efforts ahead of January national elections.
An American contractor working for KBR, formerly known as Kellogg, Brown & Root, was killed and a U.S. soldier was wounded during a pre-dawn mortar and rocket barrage Tuesday at a garrison in Baghdad, officials said.
The three car bombs in Mosul, killing two Iraqi civilians and wounding three, occurred between 12:30 p.m. and 1:30 p.m., the military said. One bomb targeted a provincial convoy belonging to the governor of Ninevah, though he was not in the convoy himself. Another hit a military coalition convoy, causing minor injuries to one U.S. soldier.
The wave of violence that has swept Iraq has convinced many humanitarian organizations — even those that have hung on through conflicts in Africa, Asia and the Balkans — that it is time to leave.
Last month, Italian aid workers Simona Torretta and Simona Pari, both 29, were kidnapped from their Baghdad offices. They were released after three weeks in captivity.
Astrid van Genderen Stort, spokeswoman for the U.N. High Commissioner for Refugees, said it was up to each non-governmental organization whether to keep staff in Iraq.
"We, the U.N., decided last year not to have international presence anymore because we deemed the situation too dangerous for us," van Genderen Stort said. "The kidnapping of the Italian and Iraqi women only a while ago should have alerted others even more as to the dangers of operating in Iraq."
Last year, as U.S.-led forces massed for the invasion, Hassan told the Atlanta Journal-Constitution that she would not leave "because I think it's important for my staff that I stay with them. The strength comes from us supporting one another."