An Egyptian police officer has been killed and three more wounded in a drive-by shooting attack by unidentified assailants on a truck that was transferring prisoners on a desert road between the capital, Cairo, and Fayoum City.

The early Saturday incident came as the gunmen riding a motorcycle began shooting at the police vehicle that was travelling on the road to the south of the nation’s capital, local Al-Ahram news website reported citing initial investigations by Egyptian authorities.

According to the report, those injured in the fatal attack were transferred for treatment to the General Hospital of Fayoum, nearly 100 kilometers southwest of Cairo.

The Cairo-Fayoum desert road, the report adds, has been disrupted multiple times in the past by armed militants that targeted security checkpoints.

Armed attacks on police checkpoints and other security facilities by anti-government militants have been common across Egypt over the past two years since the country’s military, led by then army chief and now President Abdel-Fattah al-Sisi, ousted the nation’s first democratically-elected president Mohamed Morsi in a military coup.

Since Morsi’s July 4, 2013 ouster, Egyptian forces have cracked down on pro-Morsi protesters and the Muslim Brotherhood organization, killing hundreds and arresting tens of thousands of demonstrators, some of whom have been sentenced to death or served with long prison terms in mass trials.