The remains of 34 Ethiopian Christians killed by the Islamic State group in 2015 have been found in a mass grave, a branch of the interior ministry said on Monday.

ISIS jihadists published a video in April 2015 showing the execution of at least 28 men, described as Ethiopian Christians.

An official said on Monday their bodies have been discovered near Sirte, the jihadists' former stronghold until they were ousted from the coastal city in December 2016 by forces loyal to Libya's UN-backed government.

Taha Hadid, spokesperson for the Sirte protection force, told AFP that the bodies of 34 Ethiopians were discovered on Sunday at a farm near the city.

"According to the prosecutor general's office, these remains belong to the Ethiopians executed" by the Islamic State group, he added.

The mass grave was discovered through confessions made by ISIS members captured during the battle to retake Sirte, according to the organised crime department in Misrata to the west of Sirte.

"The bodies will be repatriated to Ethiopia once the national and international legal procedures are completed," the department said in a statement posted on Facebook.

The remains of 21 Coptic Christians killed by ISIS in February 2015 were found last year near Sirte, all but one Egyptians, but their bodies were only returned home in May 2018.

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