BAGHDAD, Iraq – Gunmen seized the director of CARE International, a woman who has worked on behalf of Iraqis for three decades.

Elsewhere Tuesday, a mortar attack killed at least four Iraqi national guardsmen 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 in her early 60s, was kidnapped while being driven from her home to CARE’s office in a western neighborhood of the capital, according to a CARE employee.

Early today, CARE Australia, which coordinates the international agency’s Iraq operations, announced it had suspended operations because of the abduction, but it said staff would not be evacuated.

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. The tape did not identify what group was holding her and contained no demand for her release.

Hassan, who was born in Dublin, is married to an Iraqi and has lived here 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 after the Gulf War, with programs focusing on rebuilding and maintaining water and sanitation systems, hospitals and clinics.

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, Iraqi and multinational officials said.

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 killed two Iraqi civilians and wounded three, 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.

Meanwhile, Fallujah negotiators are ready to resume talks with the Iraqi government to avert an all-out U.S. assault and allow Iraqi forces to take charge of security in the rebel-held city, a negotiator said Tuesday.