A look at Pakistan's restive tribal area

Key facts about Pakistan's northwestern tribal regions bordering Afghanistan, which have become a haven for al-Qaida and Taliban-linked militants.

GEOGRAPHY: The rugged area stretches about 280 miles from the foothills of the Hindu Kush mountains in the north toward the southern deserts of Baluchistan, opposite Taliban-infested eastern regions of Afghanistan where U.S. forces are based.

Known as the Federally Administered Tribal Areas, the region consists of seven distinct districts — Bajur, Mohmand, Khyber, Kurram, Orakzai, North Waziristan and South Waziristan.

POPULATION: According to the last national census in 1998, the region has a population of around 3.1 million people, mainly ethnic Pashtuns, the same ethnic stock as the Taliban in Afghanistan.

HISTORY: Since the British colonial era, the region has seen fierce armed resistance to foreign or government intervention, driven by a strong pride in their independence but also criminality and militancy.

Britain controlled the region through cooperative tribal elders who had to deal with its agents, a system that Pakistan maintained but which has been undermined by the rise of Islamic militants.

MILITANCY: The region became a sanctuary for Taliban and al-Qaida fighters — and possibly terror leaders Osama bin Laden and Ayman al-Zawahri, after they fled U.S. bombardment of Afghanistan in late 2001.

In the past two years, Taliban militants have grown in strength and expanded into other parts of northwestern Pakistan. The government has deployed about 100,000 troops in the tribal regions, but has struggled to maintain order and has lost hundreds of soldiers in fighting.