Two Egyptian tribesmen were also killed after ISIS claimed they had been fighting with Egyptian forces.
The footage released by the Egyptian terror group that is linked to ISIS showed a militant with his face blurred and an AK-47 slung across his chest.
The militant had his index finger raised to the sky and warned the “Christians of Egypt” that “this is the price you pay for supporting the Egyptian army”.
These tribesmen are also accused of siding with the Egyptian armed forces.
The Coptic Church in Egypt said that Mr Salama went missing last November.
It is thought that he was kidnapped while walking along the streets of Bir al-Abed by jihadists in a car.
A spokesman for the Coptic Church said he had been involved in rebuilding churches destroyed by Islamists in the region.
The spokesperson for the Coptic Church said Mr Salama, “kept the faith till the moment he was killed”.
The spokesperson added: “The church affirms its steadfast support of the Egyptian state’s efforts in quelling hateful terror acts.”
The jihadists have been carrying out a long-running insurgency in the North Sinai region of Egypt since 2013.
They have been targeting Egyptian army personnel since the military overthrew Egypt’s elected Islamist president Mohamed Morsi.
The jihadist group has used the Sinai Peninsula to strike elsewhere in Egypt.
One such attack was the bombing of a Christian chapel next to the Coptic cathedral in Cairo in 2016.