When spring came and the snows began to melt in the mountains of Waziristan, Pakistani troops braced themselves for the seasonal upsurge in fighting along the porous border with Afghanistan.

But, when it came, Pakistani soldiers were surprised, and relieved, to see the Taleban loyalists and the militants linked to al-Qaeda who seek sanctuary in this lawless region firing rockets and mortars not at them but at each other.

For the first time since 2001, the Waziri tribesmen who probably harboured Osama bin Laden and remain loyal to the Taleban are fighting against the foreign militants in their midst.

In the past two weeks an estimated 250 people have been killed in fighting between the tribesmen and militants, who are mainly from the former Soviet Central Asian state of Uzbekistan.

A council of tribal elders in South Waziristan is said to have declared jihad (holy war) against the Uzbeks, and beat traditional war drums to raise a lashkar, or militia. According to local traditions, any man of fighting age who does not join the militia will face a fine and have his house burnt down.

The fighting is a rare piece of good news for General Pervez Musharraf, the President of Pakistan, as he prepares for a presidential election this year and parliamentary elections in early 2008.

In the past month his authority has been challenged by lawyers’ protests over his suspension of the Chief Justice, and a Taleban-style campaign by radical clerics to “cleanse” Islamabad, the capital.

General Musharraf has also faced mounting criticism over the peace deals that he signed with tribesmen in Waziristan after sending troops into the area in 2004.

US officials say the deals caused an increase in militant incursions into Afghanistan. But Pakistani officials now say that the deals have helped to drive a wedge between the tribesmen and their “guests”. Their claims are hard to verify or disprove.

But the origins of the fighting appear to be more complex and its long-term consequences less clear-cut than Pakistani authorities are making out.

Sources familiar with the region say that the conflict is the result of a feud between one group of Waziris and another that has been profiting from hosting the Uzbeks. In late 2001, when the Taleban was toppled, Uzbek militants who had fled a domestic crackdown into Afghanistan, then fled again over the Pakistani border into Waziristan.

Since then, they have been living among the Waziri tribes, along with several hundred Arabs, Chechens, Libyans, Moroccans and Chinese Uighurs, in exchange for money and military support.

The exact number of Uzbeks remains unclear, but estimates range between 500 and 2,500 and they are thought to be the largest and fiercest group of foreigners in Waziristan.

Security sources say that they have been involved in attacks on Pakistani troops and on Nato forces in Afghanistan. Tahir Yuldashev, their leader, is thought to have close ties to bin Laden. But the Uzbeks are more committed to their own national struggle than to global jihad.

To support themselves, they have been engaged in criminal activity, raiding banks, hijacking cars and lorries and kidnapping people in Waziristan. “They are more criminals than jihadis. People don’t consider them good Muslims,” said one Waziri from an area where many Uzbeks live.

It is unclear exactly how these tensions flared into open warfare. One theory is that Waziris opposed to the peace deals used the Uzbeks to murder dozens of maliks — or village elders — who were viewed as pro-government. Another is that the Uzbeks and their local allies killed an Arab al-Qaeda operative who was being sheltered by another group of Waziris. Whatever sparked the current fighting, a powerful Waziri Taleban commander called Mullah Nazir ordered the Uzbeks to disarm or leave the area in early March.

When they refused, he attacked the area that they were inhabiting, near the town of Wana, in South Waziristan.

Even security officials find it hard to fathom the complex web of tribal, political, financial and military allegiances that governs life in this area.

“It’s more difficult than rocket science,” a former security officer said.

For the moment, Pakistani and Western officials are simply pleased to see the tribesmen fighting against foreigners, whatever their reasons.

“Of course, it’s a positive development in an area which has not seen many for a while,” one Western diplomat said.

However, some security sources and analysts are sceptical about the casualty figures and the longer-term implications of the conflict.

“Is fighting between foreigners and locals going to lead to peace for either Afghanistan or Pakistan? No,” said Samina Ahmed, of the International Crisis Group. “Suppose Nazir’s group wins this fight — we’re back to the 1980s, when loyalties were based on the military clout of militant groups.”

Once the fighting is over, most expect Mullah Nazir and other tribal leaders to resume attacking Pakistani troops and making incursions into Afghanistan. But at least the feuding has breathed some life into the ill-fated campaign by Pakistan to control its border with Afghanistan.

As one Pakistani source put it: “It’s like being in an intensive care unit and getting a heartbeat back on the meter.”

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