The Libyan Prosecutor General said in a statement on Friday that the remains of 20 Egyptians killed by ISIS in Feb. 2015 were uncovered.

The 20 nationals were filmed as they were beheaded by militants belonging to ISIS. As a response, the Egyptian army announced it had launched eight air strikes on specific targets, including camps and ammunition stores belonging to the extremist group in Derna.

At the end of last month, Libyan officials said it arrested a suspect accused of filming the beheading of the Egyptian Copts.

Islamist militants and reportedly the Al-Qaeda-affiliate Derna Mujahideen Shura Council (DMSC) control the city of Derna, which the Government of National Accord’s (GNA) army has been trying to seize. However, ISIS militants were still in Derna by the time the 2015 joint strike took place.

After the incident, President Abdel Fattah el-Sisi called on the U.N. Security Council for international intervention in Libya. The Security Council stressed in a statement that ISIS must be defeated “and that the intolerance, violence, and hatred it espouses must be stamped out.”

In April 2016, the DMSC announced that ISIS militants have been forced out of Derna after the armed conflict that occurred between the two groups, according to the British Broadcast Corporation.

In 2014, Egypt’s diplomatic staff members were evacuated from Libya as a security precaution that the Egyptian ministry affirmed would not impact upon relations with the neighboring country.

Egypt has strong ties with the Libyan Government of National Accord, as Sisi met earlier in May with Haftar, and stressed the importance of the support of the national army in combating terrorism, as well as seeking a peaceful solution in Libya.

There have been reports about several cases of Egyptian nationals being kidnapped in Libya following the intensification of clashes between the two warring governments in the oil-rich country. The lapse in power structures in Libya has allowed ISIS-affiliated groups to gain control over large swathes of land.

This article has been adapted from its original source.