Egypt launched its second round of airstrikes on Islamic State group targets in Libya on Monday, part of the country’s revenge on the militants for executing 21 Egyptian Christians. Airstrikes targeted militant positions in Libya’s port city of Derna, according to CNN.

The militant group formerly known as ISIS released a video on Sunday purporting to show the beheading of 21 Coptic Christians from Egypt whom militants had abducted in Libya. Egypt’s Ministry of Foreign Affairs banned travel to Libya on Sunday, according to Egyptian news website Mada Masr.

“[It is] Egypt’s right to defend its people’s security and stability, and bring retribution in response to criminal acts by terrorist groups inside and outside of the country,” Egypt’s Defense Council said in a statement.

The first round of Egyptian airstrikes to hit Libya after the release of the video killed 64 ISIS militants and hit 95 percent of intended targets, Mada Masr reported.

Airstrikes were conducted in coordination with the Libyan military, which is aligned with forces from former Gen. Khalifa Hifter's militia. Hifter is fighting the General National Congress, made up of Islamist militants aligned with an extremist movement called Libyan Dawn, also known by its Arabic name Fajr, which seized the capital last summer and announced its own government.

This isn’t the first time Egypt has coordinated actions with Libyan army forces. Egyptian president Abdel Fattah el-Sisi has expressed concern that the Libyan civil war would spill over the border since he took power in 2014, and has long accused Libyan smugglers of bringing weapons into Egypt and selling them to Egypt’s own jihadist group and the Muslim Brotherhood, a Islamist group led by ousted Egyptian President Mohammed Morsi. Egypt has now declared the Brotherhood a terrorist organization.

However, Egypt’s ISIS woes are not limited to Libya. Last year, Egyptian jihadist group Ansar Bait al-Maqdis, which is active in the Sinai Peninsula, pledged allegiance to ISIS and has claimed responsibility for multiple attacks on Egyptian security forces.

"Avenging Egyptian blood and punishing criminals and murderers is our right and duty," the Egyptian military said in a statement broadcasted on state-run television on Monday.