New U.S. commander Gen. David Petraeus arrived in Afghanistan Friday, a day marred by violence in a part of the troubled nation that was relatively peaceful a year ago.
Petraeus arrived at NATO headquarters in Kabul in the evening, the International Security Assistance Force said.
Earlier in the day, Taliban militants in the northern city of Kunduz attacked the compound of a U.S. aid agency subcontractor, killing at least five people and wounding 20 others, government officials said.
On the day of Petraeus' arrival, the brazen attack served as a grim reminder for international forces that they faced a difficult challenge in overcoming the Taliban insurgency, which many say has been gaining momentum. A year ago, places like Kunduz were regarded as safe - but not anymore.