Afghan officials say a bomb targeting a fuel truck has exploded north of the capital, Kabul, killing at least three people.

The officials said the blast happened Wednesday in Parwan province as a crowd of people gathered around the truck. The explosion wounded about 50 people.

Earlier Tuesday, the Afghan government urged 600 religious scholars and mosque leaders taking part in a three-day conference in the capital, Kabul, to participate in an anti-drugs awareness campaign.

The Anti-Narcotics Ministry Tuesday said the use and cultivation of any type of drugs is forbidden in Islam, and religious leaders can highlight that fact in their daily and weekly sermons.

It expressed hope that the participants will issue an Islamic religious edict, or fatwa, and emphasize a greater role for religious scholars and leaders in eliminating the use of drugs inside Afghanistan.

Also Tuesday, NATO said joint Afghan-coalition forces intercepted a large shipment of drug-processing materials in southern Kandahar province, containing more than 21 tons of morphine, ammonium chloride and sodium carbonate.

A NATO statement said joint security patrols also killed several insurgents and detained numerous others, including two Haqqani facilitators, in the last 24 hours across the country.