The events leading to the current fighting in Kargil in the north of Kashmir have been subject to the usual claims and counter claims by India and Pakistan.

But the latest outbreak of fighting along the Line of Control is one of the most serious in recent years, and India says the unidentified infiltrators are not acting alone.

The latest round of fighting has broken out in one of the most inhospitable places in the world. For six months of the year heavy snows make it uninhabitable.

The two sides have made claim and counter claim

While there are annual skirmishes along this section of the Line of Control, they usually only only last for two or three days and militants are often reluctant to engage the Indian forces in heavy fighting. Now that seems to have changed.

Reports from the Indian army say "infiltrators" are holding a 10km stretch about 6km within the Indian side of the demarcation line. This area includes the Dras and Kargil sectors along the Batelik mountain range.

Claims of Pakistani involvement

At first, the Indian army claimed these infiltrators were militants on a suicide mission in the region.

One such group, the Tehrik-e-Jihad, came forward over the weekend to claim responsiblity for the incursion.

Now the Indian authorities say they have proof that while militants are involved, they have heavy back-up from the Pakistani army.

Information from the area is restricted, but India's high-command says the fighters in Kargil probably moved in as early as the end of April. There are unconfirmed reports that Indian troops usually stationed in the area were not at these high posts because of the bad weather.

The early thaw in the area meant the infiltrators could press on with their operation into Indian territory. India controls two thirds of Kashmir, Pakistan controls the remaining third.

Three months of fighting

The fact that they have been able to take such a high position - about 5,000 metres - in such hostile terrain means that any offensive launched by India might incur heavy losses for the Indian army.

India's army now says it is faced with the prospect of the fighting in Kargil lasting at least three months as they try to push the infiltrators back over the Line of Control.

Pakistan maintains that India has used the reports of infiltrators as a pretext for stepping up its presence in the area. India has some 30,000 troops in the area including special forces and paratroopers.

Reports that the Indian army was considering airstrikes as the only effective way of flushing out the infiltrators have led to fears of an escalation in the cross-border tensions, but Pakistani officials have made it quite clear that they are ready for anything in the face of Indian agression.

Pakistan and India continue to play the game of claim and counterclaim.

While India believes Pakistan is behind the incursion, Pakistan maintains that the militants are acting alone.

As the fighting continues, who exactly is involved may become clearer.