Updated

Egypt's military says that three officers and one soldier were killed when a suicide belt went off as forces were sweeping a militant hub in the Bahariya Oasis in Egypt's western desert.

Military spokesperson Tamer el-Refaie said on his Facebook page Wednesday that the incident took place during ongoing military operations in the western desert bordering Libya.

Egypt's western desert has been the scene of numerous terrorist attacks in recent years, including an attack on a border guard post in 2014 which left at least 21 troops dead. President Abdel-Fattah el-Sissi blamed Libya-trained terrorists for the recent attack on a bus carrying Christians in Upper Egypt, which killed 29.

Egypt has a long, porous border with Libya, which officials say is a route for smuggling in arms and fighters.