Stars Tweet For Kidnapped Nigerian Schoolgirls
Celebrities and public figures have been using social media to tell their millions of followers about the kidnapped Nigerian schoolgirls.
Twitter has been the epicentre of the campaign, with the #BringBackOurGirls hashtag building up momentum in the last week and trending worldwide.
Michelle Obama became one of the most high-profile people to highlight the kidnappings when she tweeted a picture from the White House.
"Our prayers are with the missing Nigerian girls and their families," said the First Lady.
The post from her @FLOTUS account has been retweeted and favourited nearly 60,000 times during the first 12 hours.
Malala Yousafzai, the Pakistani schoolgirl who survived being shot by the Taliban for promoting girls' education, has also posted a picture of herself holding a sign.
The 16-year-old, who was nominated for the Nobel Peace Prize and now lives in Britain, told CNN the girls were like "sisters" to her.
The hashtag was started by Nigerian lawyer Ibrahim M Abdullahi on April 23, nine days after the 276 girls were taken from their school in the north of the country.
It has also made the jump into the "real world", becoming a convenient slogan for posters and placards of campaigners on the ground - who have adopted red as their chosen colour.
Supermodel Naomi Campbell is another of the famous faces promoting the #BringBackOurGirls hashtag.
In an Instagram post she called on under-fire President Goodluck Jonathan to "do something!!!".
The Nigerian leader has been criticised for not doing enough to track down the girls, who are thought held captive by Islamist group Boko Haram in a sprawling forest in the northeast of the country.
Musicians Chris Brown, Puff Daddy, Leona Lewis, Mary J Blige and Alicia Keys have also jumped on board.
R&B singer Brown urged his three million followers to "lend a voice by asking authorities to #BringBackOurGirls", while UK X Factor winner Lewis posted an image of herself holding a sign.
A Facebook campaign also wants people to flood Twitter, Facebook, BBM, Instagram and Whatsapp for 200 minutes on Thursday to add more momentum to the campaign.
An online petition on the Change.org site has so far notched up more than 500,000 names and is aiming for one million.
As social media campaign gains momentum, the Nigerian government has called on international experts in areas such as hostage negotiation and intelligence to help track down the girls.
Mr Jonathan has said the kidnap will mark the "beginning of the end" of terrorism in his country - but for hundreds of families still without their daughters that will be little consolation.