The family of Glen Lapp, 40, of Lancaster, was told of his death Sunday morning, according to the Mennonite Central Committee.
Those killed in the attack Thursday were part of an International Assistance Mission providing eye care and medical help. The Taliban has said it was responsible for the killings, alleging that the workers were trying to convert Afghans to Christianity. Family and friends of the victims deny that.
Lapp went to Afghanistan in 2008 and was to remain until October, the mission said. Although trained as a nurse, he was not working as a medic in Afghanistan but served as executive assistant for the mission and manager of its provincial ophthalmic care program, spokeswoman Cheryl Zehr Walker said.
"Where I was (Afghanistan), the main thing that ex-pats can do is to be a presence in the country," Lapp wrote in a report about his term. "Treating people with respect and with love and trying to be a little bit of Christ in this part of the world."
Lapp was a graduate of Eastern Mennonite University and had a nursing degree from Johns Hopkins University, the committee said. He also volunteered for relief efforts for hurricanes Katrina and Rita and worked as a nurse in Lancaster, New York City and Supai, Ariz.
Lapp's mother, Mary, said the family was referring all calls to the committee.