The rape and murder of Zainab, a six-year-old girl from Pakistan, has sparked an outpouring of rage and grief online.
While the story has triggered angry demonstrations on the streets, more than half a million social media users have rallied around the hashtag #JusticeForZainab to call for action to be taken by the authorities, and to discuss the wider problem of sexual assault and the murder of children.
The body of the young girl was found in a rubbish dump in the city of Kasur, in the Punjab province, several days after her disappearance.
At time of writing, #JusticeForZainab has been used over 600,000 times on Twitter since 9 January and variations of the hashtag have been used more than 30,000 times on public Instagram posts in the same period.
The hashtag began trending around the world as the news of the attack came to light, and received more attention after two protesters were killed by police.
While much of the reaction expresses horror and sadness, the origins of the hashtag seem to be political.
http://www.bbc.com/news/blogs-trending-42646151
#JusticeForZainab was first used by activists for the opposition party Pakistan Awami Tehreek (PAT). The party is fiercely opposed to the ruling Pakistan Muslim League who control the Punjab province.
PAT campaigner @AtiqRehmanPAT was among the first to tweet the hashtag at 16:33 GMT on 9 January, saying the girl was "brutally abused and then silenced forever."