A major assault was launched by United States and Afghan forces against insurgents holed up in the Tora Bora region, security sources announced on Thursday.

The operation was initiated on Wednesday, air and ground troops pounding al-Qaeda and Taliban positions in the mountainous region where Osama bin Laden took shelter during the invasion of Afghanistan back in 2001.

Hundreds of troops were deployed in the region located 10 kilometers north of the border with Pakistan, reports from the country informing that Pakistani security forces were also sent to the strip neighbouring Afghanistan in order to seal off escape paths for the insurgents.

”It is a joint operation conducted by Afghan and U.S. forces, divided by ground and air assets,” said the spokeswoman for the US-led coalition forces, Captain Vanessa Bowman.

“This region has provided an ideal environment to conceal enemy support bases and training sites, as well as plan and launch attacks aimed at terrorizing innocent civilians, both inside and outside the region,” she added.

The cave complex was built by mujahideen during the Soviet invasion in the 1980s and served as a stronghold for Taliban and al-Qaeda fighters in 2001. The coalition forces assaulted the region in order to rout out remaining extremist elements and capture the al-Qaeda leader, but after the insurgents were overrun there was no trace of Osama bin Laden.

According to the spokeswoman, the military operation is based on intelligence information regarding the precise location of enemy positions and accurate fire was opened in order to avoid civilian casualties.