Sikhs celebrate founder Guru Nanak's birth anniversary

It is one of the biggest birthday celebrations in the world: millions of Sikhs mark the 550th birth anniversary of the founder of their religion, the Guru Nanak. The annual celebration has been given extra significance this year with the opening of the Kartarpur Corridor, a secure, visa-free passage between arch-rivals India and Pakistan that gives Indian Sikhs access to the place where the guru died in 1539, now one of the religion's holiest sites.