Gunmen on a motorcycle fired on Egyptian wedding guests outside a Coptic Christian church in a Cairo suburb killing two people and Injuring seven.
The assailants shot randomly at the people as they left the church, the sources said. It was not immediately clear if the two people killed were Christians, they said.
A Coptic priest at the wedding said he was inside the church when gunfire broke out.
Thomas Daoud Ibrahim said he rushed outside to find a dead man, a dead woman, and "many injured".
Coptic Christians make up 10% of Egypt's 85 million people, and have generally coexisted peacefully with majority Sunni Muslims for centuries, despite bouts of sectarian tension.
But the army's overthrow of elected Islamist President Mohammed Mursi on 3 July has been followed by the worst attacks on churches and Christian properties in years.
The immediate trigger for the attacks was a bloody security crackdown in Cairo on 14 August.
Police dispersed two Islamist protest camps set up to demand the reinstatement of Mr Mursi, and killed hundreds of his supporters.