Footage released by CNN shows men being sold at an auction in Libya.

The footage shows an auctioneer standing in front of a group of young men, shouting: “Big strong boys for farm work. 400? 700? 800?”

CNN traveled to Libya to verify the authenticity of the footage. There, they secretly filmed an auction outside the Libyan capital of Tripoli.

Referred to as “merchandise,” the men being sold into slavery were migrants and refugees. Twelve Nigerian men were sold at the auction.

“Does anybody need a digger? This is a digger, a big strong man, he’ll dig,” one salesman said.

“Within minutes it is all over and the men, utterly resigned to their fate, are being handed over to their new ‘masters,’” CNN reported.

CNN was informed of the location of nine auctions. However, “there are believed to be many more.”

In a statement, the International Organization for Migration (IOM) recently recounted the story of an unnamed Senegalese migrant sold into slavery.

According to the IOM, the migrant “described being ‘bought’ and then being brought to his first ‘prison,’ a private home where more than 100 migrants were held as hostages.”

“He described dreadful sanitary conditions, and food offered only once per day. Some migrants who couldn’t pay were reportedly killed, or left to starve to death.”

A crackdown on people smuggling by the Libyan coast guard has led to an oversupply of refugee passengers expecting to be smuggled, by boat, into Europe.

The European Union’s decision to tighten its borders has also contributed to a backlog of migrants and refugees in Libya.

Those stranded in Libya are forced into slavery by people smugglers. According to the UN, there are approximately 700,000 migrants in Libya.

Migrants who become slaves and are rescued are generally forced to return home empty-handed.

CNN told the story of a man named Victory, who left Nigeria for Libya, intending to travel to Europe for a better life. Having been sold into slavery in Libya, he was released after his family paid ransom.

He was then held by Libyan authorities, prior to his relocation back to Nigeria. “I’m not happy,” he told CNN. “I go back and start back from square one. It’s very painful. Very painful.”

In a statement, the United Nations has called for “urgent action to end [Libya’s] trade in enslaved people.”

“It is now clear that slavery is an outrageous reality in Libya. The auctions are reminiscent of one of the darkest chapters in human history, when millions of Africans were uprooted, enslaved, trafficked and auctioned to the highest bidder.”

The issue has received international attention, partly due to the influence of star football player Paul Pogba on Instagram.

“While very happy to be back, my prayers go to those suffering slavery in Libya. May Allah be by your side and may this cruelty come to an end,” Pogba posted on Instagram.

“There has been a 100-fold increase in interest in this after the simple gesture Pogba made,” IOM online communications chief Itayi Viriri told Goal.