A bomb fixed to a bicycle exploded seconds after the convoy passed south of Jalalabad, the capital of Nangarhar province on the border with Pakistan, provincial police spokesman Ghafor Khan told AFP.
"One civilian was killed and five were wounded in the bomb explosion," Khan said.
He blamed the attack on the "enemies of peace and stability", a term often used by Afghan authorities to refer to loyalists of the fundamentalist Taleban regime toppled in a US-led invasion in late 2001.