KABUL, Afghanistan (CNN) -- The Taliban said its gunmen opened fire on an aid group's vehicle in eastern Afghanistan on Wednesday, killing four International Rescue Committee workers and prompting the organization to suspend its operations.
Three IRC female staffers -- a British-Canadian, a Canadian, and a Trinidadian-American -- were killed, as well as an Afghan driver who also worked for the New York-based aid group, the IRC said in a statement.
Another Afghan driver was critically wounded in the attack in Logar province, south of Kabul, IRC said.
"They were traveling to Kabul in a clearly marked International Rescue Committee vehicle when they came under fire," according to the statement.
The Taliban claimed responsibility for the attack. The aid workers were in a two-car convoy when gunmen opened fire on them in Pul-i-Alam, the capital of Logar, according to provincial governor Abdullah Wardak.
IRC, which provides relief to refugees and victims of armed conflict around the world, said it "has suspended its humanitarian aid programs in Afghanistan indefinitely."
"We are stunned and profoundly saddened by this tragic loss," said IRC president George Rupp.
"These extraordinary individuals were deeply committed to aiding the people of Afghanistan, especially the children who have seen so much strife. Words are inadequate to express our sympathy for the families and loved ones of the victims and our devoted team of humanitarian aid workers in Afghanistan."
Earlier this month, aid groups in Afghanistan issued a report that said 19 of their workers have been killed in the country this year. The deaths Wednesday add to the count.
The groups, in a report issued by the Agency Coordinating Body for Afghan Relief, said the attacks have forced them to scale back on relief work.
"This year there have been over 84 such incidents, including 21 in June, more than in any other month in the last six years," the report said. "So far this year 19 NGO (non-governmental organization) staff have been killed, which already exceeds the total number of NGO workers killed last year."
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