Why Indian men have been 'beaten up over moustaches'?

People across India are changing their avatars and displays on Twitter and WhatsApp in support of two men attacked for having moustaches.

Last week, a young man in Gujarat went to the police and accused some upper caste men of beating him up because he'd grown a moustache. Late on Tuesday, his cousin was knifed, reportedly by the same men.

Both men belong to the Dalit (formerly untouchable) caste. Their alleged attackers have been reported as being Rajput men from a high status in India's caste system of social stratification.

It is claimed that the Rajput men objected to men of a lower caste having moustaches.