Pakistan has registered 525,000 Afghans on its soil as part of a new campaign to address the problems of war refugees, illegal immigrants and Taliban infiltrators, the government said Thursday.

The registration, which includes taking photos of Afghans and issuing identification cards, marks an important milestone for a national database launched Oct. 15, the Foreign Ministry said. There are some 2.4 million Afghans believed to be in the country.

Of the 525,000 Afghans registered by Thursday, more than half were in the North West Frontier Province that envelops the remote and rugged borderlands between Pakistan and Afghanistan.

Click here to visit FOXNews.com's Asia center.

The area is a flash point for regional tensions and believed to harbor Taliban and Al Qaeda militants and sympathizers. Usama bin Laden is thought to be hiding in the area.

The issue of Afghans in Pakistan stretches back to the 1979 Soviet invasion of Afghanistan, which triggered a wave of refugees. In recent times, it has strained ties between Afghanistan and Pakistan, both key U.S. allies in the war on terror, amid suspicions that Taliban militants slip back and forth across the porous border.

Documenting Afghans in Pakistan is expected to help address security concerns, pave the way for the deportation of illegal immigrants and identify legitimate refugees.

The Foreign Ministry said about 19,000 Afghans are being registered daily at 60 sites nationwide. Only Afghans who are registered will be entitled to stay in the country.

Pakistan and the U.N. High Commission for Refugees had earlier signed an agreement on the registration of Afghan citizens in Pakistan as part of efforts to document and manage the Afghan population in Pakistan.

More than 2.87 million Afghans have returned from Pakistan to Afghanistan with UNHCR assistance since the U.S. ousted the Taliban government.