The remains of 20 Coptic Christians beheaded by the Islamic State in Libya three years ago were reportedly transferred back to Egypt earlier this week.

The bodies reportedly arrived at the Cairo International Airport on Monday via a private plane from Libya. As many as 22 ambulances waited at the airport to transport the remains to the Zeinhom Morgue, according to Ahram Online.

Pope Tawadros II, the head of the Coptic Church, was reportedly at the airport to receive the remains of the beheaded Christians.

The Christians were kidnapped by ISIS on separate occasions between December 2014 and January 2015, before they were beheaded on a beach near the city of Sirte. Many of the victims come from poor families and risked their lives to find work in Libya amid the civil war following the downfall of Muammar Gaddafi.

ISIS executed 21 people in the massacre, which was recorded in a video released by the terror group in February 2015. A victim from Ghana was reportedly not among the bodies that were flown back from Libya to Cairo.

Agence France Presse reported back in October that Libyan authorities found the bodies in a mass grave south of Sirte after confessions from captured ISIS members.

"The heads are separated from the bodies clad in orange jumpsuits, hands bound behind the back with plastic wire," the interior ministry said at the time.

Reuters reported that the remains were recovered in October in an area once controlled by ISIS. DNA samples taken from the families of the victims will be used to identify the remains, which are expected to be buried in Egypt's Minya province.

The video of the beheadings prompted Egypt to launch air strikes against jihadist bases in Libya.

In September, an Egyptian court sentenced seven people to death in connection with the beheadings. The suspects were accused of being part of an ISIS cell in Marsa Matruh, northwest Egypt. An unspecified number were charged with participating in the beheadings.

In 2017, the family members paid tribute to the victims and voiced pride in how they refused to renounce their faith despite being threatened with death.

"I'm very happy that my brother is in Heaven with Jesus now. I loved my brother when he was alive on the earth, but now I love him more than before. He was martyred in the name of Jesus Christ," one family member said, according to International Christian Concern (ICC).

One father noted that Christian churches "were built on the blood of the martyrs at all times."

"We are very proud of our martyrs. They have lifted our heads and the heads of all Christians. The whole world witnesses them," the father went on to say.