For eight days in 1999 the world watched in horror as hijackers diverted an Indian Airlines flight to Afghanistan and held the passengers hostage, the drama ending only when Delhi agreed to release three Kashmiri militants.
Nearly 20 years later, India is still paying the price for that decision.
One of the militants freed was Masood Azhar, who later went on to found Jaish-e-Mohammad (JeM), the militant group which claimed responsibility for the deadliest attack in three decades in Indian-held Kashmir.
More than 40 Indian paramilitaries were killed in the suicide blast on February 14, kindling a fresh diplomatic crisis between nuclear-armed arch-rivals India and Pakistan.
Based in Pakistan, JeM is one of several anti-Indian militant groups fighting in Kashmir which are officially outlawed in the country, but which are allegedly used by Islamabad as proxies in India.
Azhar -- who has never been declared a terrorist by the international community -- is also believed to be in Pakistan.
The US Treasury Department website still gives his home address as a location in the province's Bahawalpur district, although his exact whereabouts remain shrouded in mystery.
- Motivator and recruiter -
He was born the son of an elementary school teacher in Punjab province in 1968, according to Amir Rana, a security analyst who has carried out extensive research on Pakistani militant groups.
Azhar originally entered Indian-held Kashmir on a Portuguese passport, security officials there told AFP, and established contact with numerous militant groups.
A common figure in the streets of Srinagar, he was known for his fiery speeches, and for mediating between the many groups flocking to the insurgency.
"His greatest value for the militant groups was as a motivator and recruiter, but more significantly he displayed a good capacity to reconcile their differences," one retired official told AFP.
Azhar was detained by Indian authorities on terrorism charges in 1994. He reportedly bragged to his jailers that they would not be able to keep him in custody.
At one point, another security official told AFP, he and other militants dug an escape tunnel, and when the moment came, Azhar insisted on going first.
"But he got stuck in the narrow tunnel because of his bulky physique and the whole attempt was thwarted," the official said.
He remained in prison until the Indian Airlines flight from Kathmandu to New Delhi was hijacked on Christmas Eve in 1999, eventually landing in the southern Afghan city of Kandahar, at the time under Taliban rule.
One of the hijackers, Ibrahim Athar, was reported to be Azhar's younger brother.
- 'Lack of evidence' -
Azhar reportedly met with Al Qaeda chief Osama bin Laden and Taliban founder Mullah Mohammed Omar in Afghanistan after he was freed, Rana said.
He formed JeM in 2000, the analyst said, and a year later the group was blamed for a brazen attack on the Indian parliament in which militants killed 10 people, bringing India and Pakistan to the brink of war.
Azhar was detained and placed under house arrest, but a court in the Punjab provincial capital of Lahore ordered his release in 2002, citing "lack of evidence".
As homegrown Pakistani militant groups turned their guns on the state after 9/11, Rana said Azhar was one of the few who kept a low profile.
The group struck again in 2016, with Delhi blaming them for an infamous attack on a military base in Indian-held Kashmir that left seven soldiers dead and once more sent tensions spiralling.
Azhar was again taken into "protective custody", but never formally charged.
Last July he addressed supporters in Muzaffarabad, the capital of Pakistani-held Kashmir, by telephone from an undisclosed location, claiming he had hundreds of militants ready to fight to the death.
The speech prompted Indian authorities to tighten security at airports in anticipation of another hijacking.
Azhar, meanwhile, has not been directly heard from since.
- Chinese wall -
As well as Pakistan, JeM is also banned by the United Nations and India, while the US State Department lists it as a terrorist organisation.
However, Azhar has not been declared a terrorist, despite New Delhi and others trying several times to get the UN Security Council to name him as one, with the move blocked each time by Pakistan's ally China.
Diplomats told AFP this week that France, Britain and the US were considering a fresh push at the Security Council to place Azhar on the UN terror list -- but once more face opposition by China.