At least 18 people died and 51 were wounded Monday when a bomb exploded in a market in northwest Pakistan's Khyber tribal region, an official told Efe.

The attack took place just before midday at a bazaar in the town of Jamrud, according to Khalid Shah, an official with the regional coordinating authority.

According to media accounts, the explosion occurred near the office of the region's political administration and next to a bus stop, causing many civilian casualties.

Khyber is one of the seven tribal districts that are the habitual redoubts for the Taliban and Al-Qaeda insurgency, and clashes between these groups and the Pakistani army are frequent in the area.

Since late 2011, security forces have been fighting with different armed groups for control of the triangle formed by the tribal zones of Orakzai, Khyber and Kurram, which provide a corridor to neighboring Afghanistan and to Pakistani Taliban bastions located further to the south.

Khyber has significant strategic importance because through it runs one of the land supply routes for the NATO troops deployed in Afghanistan. EFE