Two Egyptian policemen were shot dead this morning as they stood guard at a Coptic Christian church in Minya, south of Cairo, witnesses and a local security source said.

The policemen were killed instantly after being shot by masked men, the source and the witnesses said. The website of Egypt's state newspaper Al-Ahram also reported the two deaths.

Egypt's Coptic Christmas falls on Wednesday this week and security is typically tightened at churches ahead of the holiday.

Interior Ministry spokesman Hany Abdel Latif was quoted by Al-Ahram as saying Tuesday's attack on the policemen was not sectarian. "[It] has nothing to do with any of the holidays of our Coptic brothers, it is instead aimed at the security forces, to try to undermine their resolve."

According to the Ma'an News Agency in Cairo one of the victims was Coptic, identified as 59-year-old Eid Fahim. The other victim was named as Muhammad Abu Zeid.

Ma'an also reported that the pastor of another Coptic church in the region was shot in an unrelated attack.

Egypt's Coptic Christians make up about 10 percent of the population of 85 million and have largely coexisted peacefully with the majority Sunni Muslims for centuries.

But following the army's ousting of President Mohamed Mursi of the Muslim Brotherhood in July 2013, a number of churches and Christian properties were burned and destroyed in the impoverished south that is home to many Christians.

The Brotherhood said at the time it had nothing to do with attacks on Christians and accused the army of cynically using the minority population to justify a fierce security crackdown.

The most populous Arab nation faces a jihadist insurgency that has killed hundreds of soldiers and policemen since Mursi's overthrow. A group of Sinai-based militants has pledged allegiance to Islamic State, the al Qaeda offshoot that controls parts of Iraq and Syria.

Four years of political turmoil since the 2011 uprising that toppled autocrat Hosni Mubarak has battered Egypt's economy and frightened off tourists and investors.

Additional reporting by Reuters.