Twenty years ago, Amritsar was the stage for a bloody attack on Indian unity with consequences that still reverberate today.

Sikhs around the world remember it as their very own 9/11, their worst trauma in modern history, Operartion Blue Star, the storming of the Golden Temple in Amritsar.

It was a justified act to flush out militants, say the Indian authorities. But for many Sikhs it was a heinous defilement of their most sacred site, and the slaughter of hundreds of innocent pilgrims.

In After Blue Star, Mark Tully explores what was behind the military action. Why did it go so badly wrong? How did a separatist movement grow out of it? And how has it shaped Sikh identity all over the world to this day?

Flashbacks from people involved and those caught up in "Blue Star"

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