Trending: #JusticeforLiz and the rape that's shocked Kenya

A brutal gang rape of a 16-year-old girl was first reported in Kenya three weeks ago. But the online petition calling for justice has gained over a million signatures from around the world only in recent days. How did it suddenly get international attention?

The story could hardly be more horrific. A teenage girl, walking home from a funeral in western Kenya, was attacked and repeatedly raped by six men.

They threw her unconscious body into a latrine. Her spine was broken, and the girl - referred to simply as Liz to protect her identity - is now in a wheelchair.

Earlier this year, a similarly horrific gang rape in India sparked a worldwide frenzy in social media and brought international condemnation.

Liz's case was first reported by Kenya's Daily Nation newspaper on 7 October. "This is one of many such cases that happen in rural areas and the slums," says Njeri Rugene, the journalist who broke the story. "People keep quiet about it - but it's rampant."

The men who allegedly attacked Liz - three of whom she says she knows - were told to cut grass, then set free. The lack of punishment spurred a handful of journalists and activists to use social media to raise awareness of the case. The hashtags created did not get widespread traction, with #Justice4Liz getting just a couple of hundred tweets. But in recent days, an online petition set up by activist Nebila Abdulmelik started to gain international attention.

Two weeks ago it had just 1,600 signatures. But by Monday, it had more than one million names from all around the world. Why the sudden spike? One reason was that Avaaz, the site hosting the petition, promoted it to all members.

"I saw Nebila's tweet about it, it grabbed me and we developed it," says Avaaz campaign director Sam Barratt. The site worked with Nebila to choose the wording for the petition page, and then emailed its members, helping it stand out from about 5,000 petitions which are created each week.

"With this campaign, who could not care?" says Barratt. "Not only was the attack horrendous, but the lack of justice was clear. I think people look to see parallels of change elsewhere [such as the Indian case]. There is a real power in echoes."

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