The mountainous region of Kashmir has been a flashpoint between India and Pakistan for more than 60 years. BBC News provides a step-by-step guide to the dispute.
Why is Kashmir disputed?
The territory of Kashmir was hotly contested even before India and Pakistan won their independence from Britain in August 1947.
Under the partition plan provided by the Indian Independence Act of 1947, Kashmir was free to accede to India or Pakistan.
The Maharaja, Hari Singh, wanted to stay independent but eventually decided to accede to India, signing over key powers to the Indian government - in return for military aid and a promised referendum.
Since then, the territory has been the flashpoint for two of the three India-Pakistan wars: the first in 1947-8, the second in 1965.
In 1999, India fought a brief but bitter conflict with Pakistani-backed forces who had infiltrated Indian-controlled territory in the Kargil area.
In addition to the rival claims of Delhi and Islamabad to the territory, there has been a growing and often violent separatist movement against Indian rule in Kashmir since 1989.
What are the rival claims?
Islamabad says Kashmir should have become part of Pakistan in 1947, because Muslims are in the majority in the region.
Pakistan also argues that Kashmiris should be allowed to vote in a referendum on their future, following numerous UN resolutions on the issue.
Delhi, however, does not want international debate on the issue, arguing that the Simla Agreement of 1972 provided for a resolution through bilateral talks.
India points to the Instrument of Accession signed in October 1947 by the Maharaja, Hari Singh.
Both India and Pakistan reject the option of Kashmir becoming an independent state.
How dangerous is the Kashmir dispute?
It is potentially one of the most dangerous disputes in the world and in the worst-case scenario could trigger a nuclear conflict.
In 1998 India and Pakistan both declared themselves to be nuclear powers with a string of nuclear tests.
In 2002 there was a huge deployment of troops on both sides of the border as India reacted to an armed attack on the national parliament in Delhi the previous December. Tension between the two countries has rarely been so high.
India said the attack was carried out by Pakistani-based militants assisted by the Pakistan government - a charge always denied by Pakistan.
For much of the last two decades, separatist militancy and cross-border firing between the Indian and Pakistani armies has left a death toll running into tens of thousands and a population traumatised by fighting and fear.
Are there grounds to hope the Kashmir dispute can be resolved?
In the years prior to the Mumbai (Bombay) attacks of November 2008 - in which 174 people were killed - relations between India and Pakistan saw a big thaw.
The Mumbai attacks were blamed by India on militants based in Pakistan and led India to suspend further negotiations until February 2010, when the first formal discussions between the two countries since the attacks were held in Delhi.
Before those attacks the two countries agreed on several Kashmir-specific confidence building measures. A bus service between the two parts of Kashmir was resumed in 2005.
In October 2008 an old trade road was reopened after 60 years across the Line of Control (LoC) that divides Indian and Pakistani-administered Kashmir. Earlier in the same month a rail service was introduced.
The two governments have huge international backing to continue the peace process and make their ongoing negotiations succeed.
An end to the violence and uncertainty in Kashmir would also be widely welcomed in India and Pakistan - and not only by those weary of the fighting or those who see it as a hindrance to the economic development of the South Asia region.
However, a diplomatic solution has escaped both sides for more than 60 years, and there are no signs of any new proposals yet.
Furthermore, both governments face powerful hard line groups within their own countries who will be carefully monitoring the talks to make sure concessions they deem to be unacceptable are not offered to the other side.
Who are the militants?
Since the insurgency began in 1989, the number of armed Muslim separatists has grown from hundreds to thousands.
While many militant groups tend to come and go - or merely change their names - militancy in Indian-administered Kashmir has largely centred around three main organisations.
These are the Hizbul Mujahideen (HuM), Lashkar-e-Taiba (LeT) and Harkatul Mujahideen (HM). A late addition is the Jaish-e-Mohammad (JeM) group.
Not much is known about collaboration between the various militant groups, but most say they are members of an alliance known as the United Jihad Council (UJC).
The JeM and the LeT have achieved particular notoriety among Indians and are accused of attacking parliament in Delhi in 2001. Lashkar-e-Taiba was also blamed for the Mumbai (Bombay) attacks of 2008.
The Jammu and Kashmir Liberation Front (JKLF) was the largest pro-independence militant group, but it gave up the armed struggle in 1994 and has since been active on the political front. Its influence is thought to have waned.
Is religion an issue?
Religion is an important aspect of the dispute. Partition in 1947 gave India's Muslims a state of their own: Pakistan. So a common faith underpins Pakistan's claims to Kashmir, where many areas are Muslim-dominated.
The population of the Indian-administered state of Jammu and Kashmir is over 60% Muslim, making it the only state within India where Muslims are in the majority.
What is the Line of Control?
A demarcation line was originally established in January 1949 as a ceasefire line, following the end of the first Kashmir war.
In July 1972, after a second conflict, the Line of Control (LoC) was re-established under the terms of the Simla Agreement, with minor variations on the earlier boundary.
The LoC passes through a mountainous region about 5,000 metres above sea level.
The conditions there are so extreme that the bitter cold claims more lives than the sporadic military skirmishes.
North of the LoC, the rival forces have been entrenched on the Siachen glacier (more than 6,000 metres above sea level) since 1984 - the highest battlefield on earth.
The LoC divides Kashmir on an almost two-to-one basis: Indian-administered Kashmir to the east and south (population about nine million), which falls into the Indian-controlled state of Jammu and Kashmir; and Pakistani-administered Kashmir to the north and west (population about three million), which is labelled by Pakistan as "Azad" (Free) Kashmir. China also controls a small portion of Kashmir.
What's the UN involvement?
The UN has maintained a presence in the disputed area since 1949.
Currently, the LoC is monitored by the UN Military Observer Group in India and Pakistan (Unmogip).
So what of the future?
In the years after the 9/11 attacks in the US, Pakistan's support for militants in Kashmir diminished.
But since 2009, the militants have made a reappearance in the region and there are signs that they are growing stronger.
There is evidence to suggest the militants are now once again under the protection of the Pakistani intelligence set-up.
India for its part has reiterated that Kashmir's borders cannot be redrawn, but they can be made "irrelevant".
Since the Mumbai attacks, violence in Indian-administered Kashmir has increased, although not to the same levels as during the height of the insurgency in the mid-1990s.
An exception to that was the events of the summer of 2008, when a row over the positioning of a Hindu shrine led to protests by Muslims and Hindus alike.
The incident provided a good example of how volatile this beautiful part of the world can be - and how the capacity for violence is never far away.