KUNDUZ, Afghanistan — A NATO jet blasted two fuel tankers hijacked by the Taliban in northern Afghanistan, setting off a huge fireball today that killed up to 90 people, including dozens of civilians, Afghan officials said.

The NATO command said a "large number of insurgents" were killed or injured in the pre-dawn attack near the village of Omar Khel in the once-calm province of Kunduz. In Brussels, the alliance's chief said it was possible civilians died.

Kunduz Gov. Mohammad Omar said 90 people were killed. A senior Afghan police officer, speaking on condition of anonymity because of the sensitivity of the information, said that included about 40 civilians who were siphoning fuel from the trucks.

The airstrike is likely to intensify concern over civilian casualties in the Afghan war. Top NATO commander, Gen. Stanley McChrystal, has ordered curbs on airstrikes after a strong backlash among Afghans over civilians killed in military operations.

Afghan President Hamid Karzai issued a statement saying he was creating a panel to investigate the attack.

"Targeting civilians is unacceptable for us," he said.