Abdul Khalid, 22, a small-time smuggler who lives in a refugee shantytown here, has a new purpose in life: kill Americans.

"I have been here for several years, but now I have to go and fight because Islam is under attack," argues the one-time Jalalabad resident. "And I have a group of 28 others here who are going with me. We just need someone to tell us how it’s done."

Khalid’s is one voice in a growing, but still minority, chorus of young men and boys here who swear they are ready to take up the Taliban’s cry for jihad, or holy war.

These young zealots seek out and find their way into a murky but well-established recruiting and training pipeline that takes groups of religious students and unemployed refugees and ships them off to an unknown fate in Afghanistan with little more than their identity papers and two days’ change of clothes.

"About 20 days ago, 120 people from our group left for Afghanistan, and there are many more from here on the way," said Barkat Ullah, 21, a student at a religious school run by the Madinah Mosque in Peshawar. "I am going myself as soon as I can."

Many of the recruits come from the ranks of Pakistan’s extensive system of religious schools, or madrassahs. The madrassahs formally train students in the theological concepts of jihad, but they don’t actually order them to join the ranks.

"How many students volunteer is up to them. We can’t stop it," said an administrator at the Darul Uloom madrassah, which is run by the same religious order that instructed many of the current Taliban leaders. "We have exams this week, but after that they may be going.

"We have 1,029 students now, and I expect 400 to 500 of them to eventually go fight," the administrator said.

Those genuinely determined to sign up — and many are not, it should be noted — must get themselves to the offices of a religious association or a political group that is actively engaged in jihad recruiting. There are dozens of such associations across Peshawar, but only a few are directly involved in signing up fighters for the Taliban.

Once they find the right office and sign up, the recruits are usually told to go home and wait. After a week or more, they are contacted and told to appear at a certain place and time — without most of their personal possessions.

The recruitment offices are not hard to find, despite Pakistan’s claims that many of them have been shut down. Many are in some of the Peshawar’s more run-down areas.

One such office was located in an alley just a few yards from a spot where three men were mixing up their day’s supply of opium, which they said they had purchased in the neighborhood.

A few blocks away, on the fifth floor of a modern commercial building, a young man armed with an automatic weapon stood guard at the door of the office of J’aish Mohammed, or Mohammed’s Army. Behind the guard was a poster outlining a checklist of what recruits need to bring along on their journey: An ID card and relevant phone numbers or addresses — "you’ll be completely out of contact, and we will contact your family for you," explains the poster. Two days’ change of clothes. Don’t bother bringing tobacco, snuff, drugs.

The officials at J’aish Mohammed and the other recruitment offices refused to speak with a reporter, saying they risked being closed down by the Pakistani authorities.

The process of finding these centers and actually enlisting can be somewhat intimidating, of course, and is enough to scare away many prospective jihadis. A number of madrassah students offered what seemed to be convenient excuses for staying out of the fight, at least for now.

"I would go today, but my mother isn’t well and I must be here with her," said one 20-year-old Afghan who has lived in Pakistan for the last 10 years. "My brother is a commander in Mazar-I-Sharif and wants me to go there, but what can I do?"

Sultan Siddiqui, a Pakistani journalist and an expert in Taliban activities in the region, says it’s not the throngs of madrassah students openly parading and bragging about jihad who will eventually join the ranks of the Taliban.

It’s the quieter ones you have to worry about, he said. "The ones running around talking about it are just talking. Not many of them will go," he said.

But Siddiqui said that more young men are signing up for jihad since the U.S. bombing campaign began a week ago.

"The flow of fighters going from Pakistan to Afghanistan is much larger than the other way around," he said, discounting reports that large numbers of Taliban fighters had abandoned their positions to seek shelter in Pakistan.

"There may be some defections, but they are going to other groups rather than fleeing the country.

"The Taliban are telling them the fight has yet to begin, and that now is the time to join the war and help defeat the world’s remaining superpower."