Italy promised Monday to hold an inquiry into the killing by its soldiers of a 12-year-old Afghan girl who was shot dead while her family was on the way to a wedding, but defended the action of its soldiers. Italy's defense minister said the troops had respected all the rules of engagement, even if that still left room for a “terrible error.” Italy has said the incident Sunday occurred when the car drove at high speed and ignored warning signs. “There's deep sadness, deep regret for what has happened but unfortunately terrible episodes like this cannot be excluded when one works in an area this complex, this dangerous and this difficult like Afghanistan today,” Ignazio La Russa told radio. The youngster was killed as her family was driving into western Herat from a neighboring province for a wedding party when the troops, serving as part of the NATO-led peacekeeping force, passed from the other direction. A spokesman for Italian soldiers confirmed the shooting but said troops fearful of an attack had first warned the car to stay away from them. The girl was shot in the face, said her uncle, Ahmad Wali, who had been driving. “It was rainy and we had poor visibility. All of a sudden, I saw sparks in front of our vehicle and then a foreign forces armored convoy coming from the opposite direction,” Wali told reporters. Civilian deaths caused by foreign troops in Afghanistan have become a major cause of friction between the government and its Western backers, and sapped support for the presence of international forces in the country. Foreign Minister Franco Frattini told the Il Messaggero newspaper that Italy would investigate the shooting and make all necessary checks, but called it a tragic incident stemming from procedures Italian soldiers must follow in case of danger. “Our soldiers are obliged in the face of certain conditions – an unknown car going at a great speed, a potential danger – ... to put in to place some precise rules that all the contingents apply,” he said. Three other family members were wounded, the family said. Italy is the sixth largest troop contributor to the NATO-led military operation in Afghanistan.