Giza governor Ali Abdel Rahman said on Tuesday that his administration will offer financial compensation to the victims of the attack against Al-Adra church, or the Church of the Virgin Mary, in Cairo's working class neighbourhood of Al-Warraq.

On Sunday, four people were killed and 18 others wounded when two gunmen on a motorbike opened fire on a crowd of guests attending a wedding outside the church.

Abdel Rahman said the families of the dead will receive LE 5000 ($725), whereas each wounded will collect LE 2000 ($290), according to state news agency MENA.

All injured have been transferred to a military hospital south of Cairo, Al-Ahram's Arabic website reported the health ministry as saying.

Following massive protests against his turbulent year in power, Mohamed Morsi was toppled by the army on 3 July, sending the country into a bitter political deadlock.

Islamists, incensed by Morsi's ouster, have accused Christians of orchestrating what they call a coup against the country's first freely elected president.

Coptic Orthodox Pope Tawadros II, the leader of Egypt's largest Christian denomination, backed Morsi's ouster, appearing on television alongside army chief Abdel Fattah El-Sisi and other political and religious figures when El-Sisi announced Morsi's removal.

Coptic Christians, who make up some 10 percent of Egypt's 84 million, have long complained of discrimination and periodic violence by extremists. But the number of sectarian attacks has surged following a security crackdown on Islamists in mid-August.

Amnesty International, a London-based rights group, says that upwards of 200 Christian-owned properties have been attacked and 43 churches torched or seriously damaged across the country, adding that at least four people have been killed.

Most of the vandalism to Coptic homes, monasteries, schools, and shops, however, has occurred outside the capital, making Sunday's attack especially shocking.