AKCAKALE, Turkey — Within sight of an unoccupied watchtower, and a couple of hundred meters from the border gate at Akcakale on the Syrian-Turkish border, two small girls are skipping on stacks of piping ready for shipment to the town of Tel Abyad, now controlled by the Islamic State, or ISIS, across what the Turks claim is a locked-down frontier.

It is the weekend and so in this slow-paced, dusty border town, decorated with multi-colored banners and pennants of Turkish political parties campaigning for next month’s parliamentary polls, no one is hurrying to transport the suspicious cargo. And so here the pipes, several meters long and three inches in diameter, remain.

Around the corner there are more pipes—larger ones, six inches in diameter. Smugglers say the piping can sustain high pressure and will be used by jihadists in Syria to manufacture pipe bombs, improvised explosive devices and launch-tubes for mortars.

The 35-year-old smuggler warns me not to get out of the car. The few men lounging around are watching us intently.

A few days ago, The New York Times published an article about how large amounts of ammonium nitrate are being transported on carts across the border, into the so-called caliphate. Ammonium nitrate is used not only as a fertilizer but also as an ingredient to build powerful explosives. The town is now on edge: Local officials, who claimed at first the ammonium nitrate was just flour, are not welcoming to Western journalists. And more alarmingly, ISIS agents in the town and their smuggler-allies are said to be on the lookout for reporters. A few months ago, two freelance news photographers reported there was an attempt to abduct them—and so I content myself with filming the pipes from the safety of a car.

We have just passed seven boys sitting on a low concrete embankment overlooking unused railway tracks running alongside the border. They are waiting for three bored-looking border guards manning an old, battered armored personnel carrier to look the other way so that they can make a quick dash to the low wire fence and clamber over easily into ISIS’s self-styled caliphate. Two of them have bikes and the fence will pose no daunting obstacle to getting those across either.

In the distance, a black flag is waving above a building in downtown Tel Abyad. A new white Toyota pickup accelerates on a road on the Syrian side shadowing the border fence—the Turkish guards pay it no heed.

Today the border gate is closed, but come Monday, says the smuggler, the pipes will likely be whisked across—although not before ISIS agents, clean-shaven to avoid drawing too much attention to themselves, will inspect the goods.

Welcome to the border crossing nearest to the de facto capital of the Islamic State.

One could have expected this border gate separating NATO from the world’s first self-proclaimed jihadi state to be bristling with soldiers and guns. Turkey, after all, has the second-biggest military in the Western alliance. But the scene here wouldn’t be out of place in the old Peter Sellers comedy about a blustering mini-state, The Mouse That Roared.

Local Turkish officials claim that only Turkish-supplied humanitarian aid is going through the border gate, which is closed officially every now and then when fighting flares between Western-backed Free Syrian Army (FSA) rebel militias and ISIS. But a flare-up hasn’t happened for some time, and humanitarian aid isn’t the only thing going through the border gate.

“Depending on the thickness of the pipes, both diameter sizes could be used for mortars, but it is more likely that the three-inch ones would be used for making IEDs and pipe bombs,” says Darren White, a British defense consultant who served a quarter of a century in the British army. “And these improvised devices have been seen around in Syria and Iraq. The bigger pipes, yes, more likely to be used for launch-tubes. And the piping can be used as casing for homemade mortar bombs.”

Field investigators for Conflict Armament Research, a private arms-tracking organization in Britain, noted in a report on where ISIS gets its weapons that during the months-long siege of the mainly Kurdish border town of Kobani improvised devices were present. “ISIS forces used improvised munitions of different types in significant quantities… suggesting a lack of factory-produced, military-grade weapons in its arsenal. Most of the improvised munitions were based on mortar rounds of various calibers and 105 mm rockets containing aluminum based homemade explosives.”

Near to the piping is a large generator waiting to be sent over. And small-time local merchants, many of them owners of shabby small stores in town, are enjoying a brisk trade in exporting consumer goods impossible to get in Raqqa 60 miles away—everything from clothes to cellphones. But smugglers say business was better before the war, when they were trafficking tobacco, sugar, tea, and cement, and there was open trade between Syria and Turkey.

The locals complain the Syria war has depressed cross-border trade in this town of nondescript squat two-story buildings. But there are obvious signs that some people are doing quite nicely, thank you.

As in many of the Turkish border towns, some people clearly are profiting—or profiteering—from war. New office and residential buildings are springing up, and although the presence of Syrian refugees has depressed wages for manual and farm laborers, stores do well from the displaced. The town’s population was 90,000 before the civil war erupted across the border; it has now doubled, thanks to the refugees, half of whom are sheltered in a nearby camp and spend their food vouchers in the form of pre-paid credit cards in the local stores, which are charging them inflated prices.

The low-key Turkish security presence in Akcakale stands in marked contrast to other parts of Turkey’s 501-mile border with Syria. About 130 miles to the west, the border gate at Kilis, opposite mainly FSA units, has been closed officially since the end of March, although humanitarian aid is allowed through. Turkish border guards recently fired on Syrian refugees trying to flee into Turkey illegally through a smuggler’s tunnel near Kilis, according to a Syrian journalist who was also attempting the illegal crossing,

At Suruc, the mainly Kurdish border town adjacent to Kobani, the Turkish security presence remains high, with paramilitary gendarmes well supported by armored vehicles patrolling the streets.

But here at Akcakale, there is no serious military presence, there are no checkpoints as you enter town on the road from Urfa, the Turkish city half-an-hour’s drive away that many foreign recruits have passed through on their way to join the jihadis.

On the day I entered town, there was one police car at a roundabout as you entered the main drag and a policeman sitting on the ground with his back to the road, drinking tea with a local.

“You should understand something,” said the smuggler who showed me the stacked pipes and is using the name Ahmed for this article but, for obvious safety reasons, doesn’t want his real name disclosed. “It isn’t hard to cross into the caliphate, but go further west or east into Kurdish territory, then it gets much harder to evade the Turkish military and cross the border. Even the birds can’t come from there; and our birds can’t go there,” he says. That is an exaggeration—there are illegal crossings all along the border, but certainly it would seem, from the thin Turkish security presence, much easier here.

“They are very tough with the Kurds and the areas controlled by the Free Syrian Army, but with areas across from ISIS not so much,” he explains over a cup of tea in the sitting room of his apartment a short walk from the border. On a flat-screen TV, Turkish cartoons are playing but the sound is muted—his children banished to another room. One small girl slams the door when shooed away to join her siblings ranging in age from 6 months to 7 years.

Up until about 18 months ago, Ahmed was smuggling foreign recruits across the border, but stopped when he realized they were going to ISIS. “I thought they were going to Jabhat al-Nusra or the FSA,” he says. The fighters he guided across the border either a few miles east or west of the town, where there are easy paths through farmland and olive groves, were young, in their late teens or very early 20s.

He says of the 20-plus recruits he assisted, none were Arabs: They were Georgian, Russian, and Azerbaijani as well as three Britons and two Americans. Through an Azerbaijani, he asked the British recruits why they were going to Syria. “They said for jihad.”

In those days it was easier for foreign recruits. The foreigners would board a domestic flight from Istanbul’s international airport to Urfa or Gaziantep and then be driven to Harran, a small town 12 miles from Akcakale, where they would stay at the hotel for a few hours before being guided to Tel Abyad. Harran, once a center of Assyrian Christianity, was resettled by the Ottoman Turks during the 18th century with ethnic Arabs from what is now Syria and, as with Akcakale, Syrian Arab influence is obvious with many locals able to speak Turkish and Arabic.

Under pressure from Washington and the Europeans, Turkish authorities have become more vigilant in Istanbul and are monitoring the Gaziantep and Urfa airports.

Foreign recruits are being intercepted and their journey has become more disguised, says Ahmed. Recruits and would-be jihad brides are flying to more far-flung airports and then busing themselves to Urfa or taking a bus from Istanbul. And instead of congregating at the hotel in Harran, they are being distributed by their handlers more discretely, in safe houses in Akcakale. Once here, the chances are slim of Turkish interception. Hatay Boumeddiene, the partner of Amedy Coulibaly, the jihadi gunman who murdered Jewish shoppers at a kosher supermarket in Paris in January, slipped across to ISIS at Akcakale despite a Europol alert.

“For us, Akcakale doesn’t exist,” says Ahmed. “Locals call this town Tel Abyad, too, just like over the border. We are the same town, the same family separated by a railway line and a little fence—we have relatives over the border.” Locals, though, have mixed feelings about ISIS. Some were happy when the jihadis eventually vanquished FSA militias in Tel Abyad, relieved that the booms and crash of battle were over. Others say they have no sympathy for the jihadis.

Aside from efforts at more discretion, not much has changed since Ahmed was a people smuggler. He says five brothers and a few of their relations are the main smugglers for ISIS and will purchase items the jihadis need. Two Turks—both longtime Islamists and now members of ISIS—are the key organizers guiding foreign recruits and overseeing cross-border trade.

“One is responsible for bringing the foreigners to Akcakale; the other stays in Syria and escorts the foreigners to Raqqa.” The men are well known to Turkish authorities, locals say. The Syrian-based smuggler travels back to Turkey once a week to go to the court at the city of Adana to attest to his presence in Turkey, and then returns to Tel Abyad. He had been arrested by the Turks for smuggling and is awaiting trial. Ahmed chuckles. “But they are still able to operate,” he says.