KABUL, Afghanistan — Explosions and gunfire erupted in the mountains of eastern Afghanistan Tuesday as U.S.-led international forces and Afghan soldiers began what seemed likely to become a new, coordinated offensive against insurgents whom American officials blame for a series of recent major terrorist attacks in Kabul.
The joint operation against the Haqqani network follows months of escalating tension between the United States and Pakistan over an increasingly fearsome insurgent group that NATO says has caused the deaths of more than 1,000 Afghan civilians and coalition troops — and whose leadership reportedly enjoys safe haven over the border in Pakistan's tribal areas.
It was unclear whether any offensive involving NATO troops and hundreds of Afghan army soldiers could seriously weaken the Haqqani group, whose fighters roam a rugged, porous border region where foreign forces have struggled to make gains. But an offensive would send a message that the U.S.-led coalition is prepared to act if Pakistan doesn't crack down on the network, which NATO accuses of nearly a dozen high-profile attacks in Kabul this year — including the daylong assault on the American Embassy last month.
U.S. officials allege that Pakistan's powerful army-run spy agency, the Inter-Services Intelligence Directorate, backs the Haqqanis — a charge Pakistan has fiercely denied.
There were no signs of troop movement on the Pakistani side, locals and officials said, suggesting no plans for a complementary offensive in the neighboring North Waziristan region. Pakistan has long resisted U.S. pressure to launch an operation against extremists that use North Waziristan as a safe haven.
A senior Pakistani military official, speaking on condition of anonymity because of the sensitivity of the issue, said that Pakistanis hadn't been briefed in advance about what the U.S.-led forces were up to but were "informed upon inquiring."
Although few clear details emerged of what the U.S. and its allies were planning, rumor of the gathering forces spread a mixture of panic and bravado in Pakistan. Many North Waziristan residents believed that a surgical U.S. airstrike was imminent, while some said they were prepared to fight U.S. troops if they crossed over.
A senior NATO official dismissed the Pakistani fears, saying that the alliance wasn't authorized to operate outside Afghanistan and wasn't trying to threaten Pakistan.
"No, we're not massing on the border," said the official, who wasn't authorized to be quoted by name.
The pace of military activity in the region has been quickening for the past four days, centered around Musa Khail, a rugged district northwest of the provincial capital of Khost, near the Afghanistan-Pakistan border, said Gen. Zahir Azimi, an Afghan Defense Ministry spokesman. He described it as "part of our routine military operations in the area ... to pave the way for development and extension of central government rule."
A resident of Musa Khail, Gulab Khan, who spoke by telephone, said that fighting continued after nightfall Tuesday and that NATO forces had arrested an unknown number of armed men whom he described as civilians. Many Afghan civilians own weapons, and there was no word on whether coalition forces had captured or killed any senior Haqqani figures.
NATO and Afghan forces discovered a "weapons depot" full of small arms and seized hundreds of sleeping bags used by insurgents to camp in the mountains, said Mobarez Zadran, a spokesman for the provincial government in Khost. He said there had been no civilian casualties.
Officials with the U.S.-led International Security Assistance Force believe that the Haqqani leadership — which is allied with but independent of the Afghan Taliban — is based about 20 miles southeast of Khost near Miranshah, the capital of North Waziristan. Capt. Justin M. Brockhoff, an ISAF spokesman, said only that "operations are being conducted across the theater to solidify security gains made throughout the course of the 2011 fighting season."
U.S. officials have warned Pakistan repeatedly over alleged links between the ISI and the Haqqanis. Two weeks ago, President Barack Obama used a White House news conference to caution Islamabad that it was jeopardizing its relationship with the United States — which includes billions of dollars in military and civilian aid — by maintaining ties with Afghan insurgents.
The Haqqanis have plotted and carried out 11 of the 15 most spectacular attacks in Kabul this year, according to NATO officials. The most notorious came on Sept. 13, when fighters holed up in a half-finished high-rise showered the U.S. Embassy and ISAF headquarters with rocket-propelled grenades and assault rifle fire for almost 20 hours, killing seven civilians and wounding many others.
Two weeks ago, ISAF said that it had detained Haji Mali Khan, a prominent Haqqani commander who managed bases and had oversight of operations in both Afghanistan and Pakistan.
Haqqani attacks have undermined what NATO commanders describe as hard-won gains in the nearly two years since U.S. forces surged 30,000 additional troops into Afghanistan. While the surge helped to substantially reduce attacks on Afghan and coalition forces, insurgents have responded with a campaign of targeted assassinations and roadside bombings that have increased civilian casualties and — NATO officials privately acknowledge — made much of the country feel less safe.
Even as the coalition pushes ahead with plans to transfer security responsibilities in more areas to Afghan control, ahead of a full withdrawal of foreign troops by the end of 2014, the senior NATO official said that eastern Afghanistan still represented a major trouble spot.
"The border piece is of concern, and frankly ... that's the one we're going to have to watch closely," the official said. "How resilient will the Haqqani network be? Will that mean that we have to provide greater assistance to the Afghans in eastern Afghanistan? That, to me, is a military question."
Despite the focus on infiltration of Haqqani and other extremists into Afghanistan, the busy border crossing at Ghulam Khan, between North Waziristan and Khost, has remained open with little interruption, clogged with trucks taking flour, wood, cement and other goods into Afghanistan every day.
When the border suddenly closed from the Afghan side for three days — finally reopening Monday — it suggested to locals that something serious was about to unfold.
Ihsan ur Rehman, a student at the Degree College in Mir Ali, another town in North Waziristan, said that he feared residents would be displaced if the American-led operation expanded into Pakistan.
"We have suffered a lot for the last decade. An American operation will cause new hardship," said Rehman. "This should be settled by negotiation between America and Pakistan."
While Pakistani Taliban militants might view American soldiers coming across the border as targets, the same eagerness to fight seemed to fill ordinary tribesmen in North Waziristan.
"We have had to go to Afghanistan for jihad against the Americans. But if they come here to us, what could be better?" said Dost Tarab Khan, a tribal elder in Miranshah. "I hope they come here and give us the opportunity to fight them."
(Zohori is a McClatchy special correspondent. Jonathan S. Landay in Washington and special correspondent Saeed Shah in Islamabad, Pakistan, contributed.)
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