Has India killed a Sikh activist in Canada? | Inside Story

The killing of a Sikh activist in British Colombia has opened up a diplomatic rift between India and Canada.
Canadian Prime Minister Justin Trudeau says India may have been involved - a charge New Delhi is calling 'absurd'.
Both sides have expelled each other's diplomats and cooperation on trade and defence could be in jeopardy.
So can this tension be contained?
And what does this tell us about the plight of religious minorities in India?