KABUL // A diminished but resilient Al Qaeda, whose September 11, 2001, attacks drew the United States into its longest war, is attempting a comeback in Afghanistan's mountainous east.
The drive comes even as US and allied forces wind down their combat mission and concede a small but steady toehold to the terrorist group.
That concerns US commanders, who have intensified strikes against Al Qaeda cells in recent months. It also undercuts the US administration narrative portraying Al Qaeda as battered to the point of being a non-issue in Afghanistan as western troops start leaving.
When he visited Afghanistan in May to mark the one-year anniversary of the raid that killed Osama bin Laden, the US president, Barack Obama, said his administration had turned the tide of war.
"The goal that I set - to defeat Al Qaeda, and deny it a chance to rebuild - is within reach," he said.
As things stand, however, an unquestionably weakened Al Qaeda appears to have preserved at least limited means of regenerating inside Afghanistan as US influence in the country wanes.
The last US combat troops are scheduled to be gone by December 31, 2014, with security matters turned over to the Afghan government. "They are trying to increase their numbers and take advantage of the Americans leaving," said Gen Dawlat Khan Zadran, the police chief of Paktika province, which borders Pakistan.
Al Qaeda's leadership fled in late 2001 to neighbouring Pakistan, where it remains.
The group remains active inside Afghanistan, fighting US troops, spreading extremist messages, raising money, recruiting young Afghans and providing military expertise to the Taliban and other radical groups.
US Gen John Allen, the top commander of international forces in Afghanistan, has said that Al Qaeda has re-emerged, and although its numbers are small, he says that the group does not need a large presence to be influential.
US officials maintain that they are committed, even after the combat mission ends in 2014, to doing whatever it takes to prevent a major resurgence.
A more immediate worry is the threat posed by the growing presence of Al Qaeda and affiliated groups in Yemen, Somalia and across a broad swath of North Africa, where it is believed Al Qaeda-linked militants may have been responsible for the attack on the US consulate in Benghazi, Libya, that killed the US ambassador, Chris Stevens, and three other Americans.
US and Afghan officials say that Al Qaeda also has been building ties with like-minded Islamic militant groups present in Afghanistan, including Pakistan-based Lashkar-e-Taiba, which is blamed for the November 2008 rampage in Mumbai, India, that killed 166 people, and the Islamic Movement of Uzbekistan, which is present in the north.
US analysts say there is reason for concern that Al Qaeda is down, but not out. "They've been hit hard in a few cases, but they definitely are involved in the fight - absolutely," said Seth G Jones, a senior political scientist at RAND Corp, a US-based foreign policy think tank.
Mr Jones, a former adviser to the commander of US special operations forces in Afghanistan, recently returned from a trip to eastern Afghanistan where he learned that Al Qaeda's support network has expanded and its relations with groups such as the Pakistani-based Haqqani network are strong.
Richard Barrett, the head of a UN group that monitors the threat posed by Al Qaeda and the Taliban, said Al Qaeda fears that the Taliban will strike a deal with the Afghan government that would make the group all but irrelevant.
"So they will be doing whatever they can to assert their influence, to assert their presence" in Afghanistan, he said.
US military accounts of raids and strikes against Al Qaeda in the north-eastern provinces of Kunar and Nuristan show the group retains a command structure inside Afghanistan. On May 27, the US killed the No 2 commander in Afghanistan, the Saudi national Sakhr Al Taifi, in Kunar. But it has yet to catch up to the top Al Qaeda commander in the country, identified by US officials as Farouk Al Qahtani, who resides in Nuristan.
In the most recent strike, officials said on September 27 they had killed an Al Qaeda "facilitator", Abdul Rauf, in Kunar. He was a Pakistani coordinator of foreign fighters' movements into Afghanistan and a builder of improvised explosive devices for attacks on coalition troops.
Interviews with Afghan officials have suggested that Al Qaeda also is present in other parts of the country including the north-western province of Faryab as well as Logar province, just south of Kabul.
In interviews in Kabul and Washington, US officials said they are satisfied that Al Qaeda is so small inside Afghanistan - they put the number at between 50 and 100 fighters - that they can be contained indefinitely if the Afghan government allows US counterterrorism forces to monitor and hunt the remnants.
US and Afghan officials are working to craft talks on a bilateral security agreement that could include such an arrangement.
US commanders say they will keep up pressure on Al Qaeda to frustrate its goals, but few believe Al Qaeda will be gone before US troops leave.
"I see no evidence to suggest that it will be eliminated by 2014," said Mr Jones, the RAND analyst.