Police official Ahmad Zia Massoud said the convoy was returning on 27 January from a humanitarian mission in southern Kandahar Province when the roadside bomb exploded.
A purported Taliban spokesman claimed responsibility for the attack.
Romanian troops are part of a U.S.-led coalition force in Afghanistan. Canadian soldiers are working with a civil-military reconstruction program in Kandahar.
Separately, Afghan authorities today said that suspected Taliban militants on 27 January set fire to three primary schools in the southern province of Helmand. Officials said nobody was hurt in the fires.
(AFP, Reuters, AP)
Suicide Attacks In Afghanistan
The results of a suicide-bomb attack in Kandahar Province on January 16 (epa)
Suicide bombers have struck more than two dozen times in Afghanistan since neo-Taliban and Al-Qaeda insurgents appear to have stepped up use of such attacks following the provincial and national elections of September 2005. While sporadic until recent months, suicide bombings have killed at least 90 people in Afghanistan since late 2001 -- including the attack in the days leading up to 9/11 that left legendary Afghan mujahedin commander Ahmad Shah Mas'ud dead. For an overview of suicide attacks in Afghanistan dating back to 2001, click here.