Smoke billowed from the windows of the church and the assailants also snatched a cross from outside the building, said the officials, who spoke on condition of anonymity because they were not authorized to discuss the incident with reporters. They said the assailants escaped. There was no immediate claim of responsibility.
The attack in the town of Rafah, on the border with the Hamas-ruled Gaza Strip, comes amid unprecedented political unrest sweeping Egypt. For nearly two weeks, protesters have staged mass rallies to demand the ouster of longtime Egyptian President Hosni Mubarak.
Rafah is located in the Sinai Peninsula, where Bedouin tribesmen have clashed with security forces during the popular revolt.
Earlier Saturday, an explosion went off in a gas terminal in the Sinai town of El-Arish, causing a massive fire but no injuries. Energy officials blamed a gas leak, while security officials said an explosive device was detonated in the terminal. As a result of the fire, the flow of gas to Jordan and Israel was stopped.
Even before the uprising, there had been growing tensions between Egypt's Muslims and large Christian minority. On New Year's Day, a suicide bombing outside a Coptic church in the port city of Alexandria killed 21 people, setting off days of protests.
Barely a week later, an off-duty policeman boarded a train and shot dead a 71-year-old Christian man and wounding his wife and four others.