From the minefields around the village of Darband, a sound like distant thunder echoed through the steep mountain valleys. What I could actually hear was artillery fire raining down on this remote corner of the Kurdish region of Iraq.

But unlike the oft-reported shells coming over the border from Turkey, these high-explosive projectiles originated in Iran. The Iranian shelling started in May 2006 and has continued sporadically ever since.

Weeks of intense bombardment are followed by uneasy lulls. No shelling has been reported since early October, but no one knows how much longer the pause will last.

In recent weeks, the world has focused on Turkey's threatened operations against separatist militants of the Kurdistan Workers Party (PKK) hiding out in Iraq. The PKK wants to carve out a Kurdish homeland in the ethnically Kurdish parts of Turkey.

Meanwhile, the Iranians are targeting a group called the Party of Free Life of Kurdistan (PJAK), which calls for autonomy for the Iranian Kurds and has been carrying out attacks in Iran. Experts say it is the anti-Tehran arm of the PKK.

On Thursday, an official Iranian newspaper reported that Iranian security forces had killed three Kurdish rebels in the country's Kurdistan province bordering Iraq. It quoted a source alleging that the PJAK is directly supported by Western countries, listing the United States and Germany.

THOUSANDS DISPLACED

Regardless of the intended targets of the Iranian shelling inside Iraq, the attacks have forced thousands of Kurds from their secluded villages and away from the border areas. They are poor subsistence farmers and semi-nomadic herders. Their crops have been destroyed and their pastures incinerated by the Iranian artillery fire.

Back in August, I watched as families struggled to escape the shelling. Painfully overloaded donkeys staggered down the rocky mountain passes, with their nervous owners driving them on. A sea of sheep and goats overwhelmed the narrow road running through the local capital of Choman, as families drove their livestock away from the explosions.

None of those who have been uprooted believe the lull in the Iranian shelling is permanent. And even if they did, they couldn't return home now; the winter snows are imminent and would leave them trapped in their villages for months. Without winter feed for their animals and firewood to keep the vicious cold at bay, going back would be suicidal.

Dana Graber Ladek, a displacement specialist with the Iraq programme of the International Organization for Migration, says that in Choman sub-district alone over 550 families have fled their homes, and are renting houses or living with other families. She adds that another 100 families have been displaced from the sub-district to the north, and around 600 more from the neighbouring province to the south.

JOINT OPERATION?

Most experts don't believe that shelling remote mountain areas will have much effect on a highly mobile guerrilla group like the PJAK. So what does Iran really hope to achieve by it?

One answer could lie in Mao Zedong's famous analogy of successful guerrilla groups being like fish swimming in the sea of the local populace. Perhaps the Iranians are taking his words a little further; in evaporating water, the fish will struggle to survive.

Local sources report a large amount of cross-border movement between Turkey and Iran. They suspect that a coordinated Turkish-Iranian operation is about to be launched in the Qandil mountains of northeastern Iraq.

The prospect of a NATO member as important as Turkey contemplating joint military operations with Iran would be deeply troubling for the United States. But such an alliance is not as unlikely as it first appears.

Steven Wright, an expert in Middle-Eastern security at Qatar University, explains: "Both Iran and Turkey share interests in confronting their common enemy, the Kurdish separatist groups. This common cause may well develop into a military partnership despite clear US opposition."

U.S. concern about a strategic realignment of Turkey with Iran may help to explain last week's visit to Ankara by Secretary of State Condoleezza Rice. "The PKK is an enemy of the United States just like it is an enemy of the Turks," she said. "No one should doubt the commitment of the United States in this situation." Clearly, Istanbul does.

One of the motivations for the Iranian attacks on the PJAK in Iraq may be to demonstrate to Turkey that Iran is a more reliable ally in the fight against Kurdish militants than the United States. Washington's recent promises to share more intelligence with the Turks may prove to be too little, too late.

Whatever the real reasons behind the Iranian shelling, one thing is certain: the families it has displaced will be spending a long, hard winter away from their homes.

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