The bodies of at least 28 migrants have been recovered from a mass grave in a desert in south-east Libya, the country's attorney general said.

The grave was discovered north of Kufra, just days after another mass grave with 19 bodies was found on a farm in the same city.

Officials found the latest grave following a raid on a human trafficking site, where authorities freed 76 migrants who had been detained and tortured, the office of the attorney general posted on Facebook.

One Libyan and two foreigners have been arrested, it added.

"There was a gang whose members deliberately deprived illegal migrants of their freedom, tortured them and subjected them to cruel, humiliating and inhumane treatment," the statement said.

Images shared online - which the BBC has not independently verified - show police and volunteers digging in the sand before placing corpses in black bags.

The search in Kufra - more than 1,700 kilometres (1,056 miles) from Libya's capital Tripoli - is continuing.

The attorney general says the bodies recovered have been taken for autopsy, with investigators suspecting links to smuggling networks. Authorities are documenting the testimonies of survivors.

Last year, a mass grave containing the bodies of at least 65 migrants was found in the south-west of Libya. The International Organization for Migration (IOM) described it as "deeply shocking" at the time.

Since the overthrow of Libyan leader Muammar Gaddafi in 2011, the country has become a key transit route for migrants risking dangerous desert and Mediterranean Sea crossings to reach Europe.

Unicef has said that in 2024 the number of people who died or went missing in the Mediterranean, trying to reach Europe, surpassed 2,200.