An explosive device went off in Cairo's Abbasiya district, close to downtown Ramses Square, on Tuesday, without any casualties.
The improvised bomb detonated while explosive experts were attempting to dismantle it upon receiving reports from local residents, Al-Ahram's Arabic news website reported.
Police closed off nearby roads to traffic as forces were deployed at the bomb site.
Egypt has seen a wave of bombings and shootings, mainly against army and police personnel, over the past year and a half.
Also near Ramses, a sound bomb went off at Cairo's main railway station on 20 November. There were no injuries or damages.