Video footage of migrants sold in apparent slave auction in Libya provokes outrage

Footage of men being auctioned off as slaves in Libya has been met with outrage and the UN Secretary-General has called on the international community to "unite in fighting this scourge".

In the grainy mobile footage, unidentified men are offered up as a group of "big strong boys for farm work".

The film was obtained by CNN journalists, who later witnessed another sale of a dozen men in a courtyard outside the country's capital, Tripoli.

"Does anybody need a digger? This is a digger, a big strong man, he'll dig," the auctioneer, who is dressed in camouflage gear, is heard saying. The men were sold for as little as £300, the US broadcaster reported.

After the footage emerged, protests erupted in Paris and other cities, while Libyans expressed solidarity with the victims with the hashtag #LibyansAgainstSlavery.

The Libyan government launched an investigation into the slave auctions, but said the international community needed to provide more support if it was going to tackle the problem.

"I abhor these appalling acts and call upon all competent authorities to investigate these activities without delay and to bring the perpetrators to justice. I have asked the relevant United Nations actors to actively pursue this matter," UN Secretary-General António Guterres said in statement.

"Slavery has no place in our world and these actions are among the most egregious abuses of human rights and may amount to crimes against humanity. I urge the international community to unite in fighting this scourge," he added, saying the latest reports served as a reminder that Europe's refugee crisis needed to be addressed in a "comprehensive and humane manner".

Rights organisations have nonetheless warned that meaningful action could take a long time.

“People are rightfully outraged,” said Human Rights Watch researcher Hanan Salah. “But don’t hold your breath that anything real is going to happen.”