Jamal, a Canadian citizen, was killed when an explosive device, reportedly attached to a microphone, detonated while he was giving a speech to mark the Muslim holiday of Eid al-Adha at the Pul-i-Alam mosque.
"I am deeply shocked by this killing of a civilian, in a mosque, on one of the holiest days in the Muslim calendar," Nicholas Haysom, deputy special representative for Afghanistan and acting head of UNAMA, said in a release. "Afghans deserve peace and should be able to celebrate the Eid holidays in an environment marked by friendship and brotherhood, free from violence and bloodshed."
The United Nations said seven other civilians were wounded, including the mosque's imam.
No one has yet claimed responsibility for the attack.
The assassination of Jamal was one of the first major targeted killings so far this year in which a higher ranking government official died, The New York Times said. Jamal, who previously was governor of Khost province, returned from Canada to take the position in April.
He enjoyed a good working relationship with coalition commanders, the Times said.
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