QENA - Thousands of Egyptians on Friday demanded the sacking of three provincial governors who had served in the police force of deposed President Hosni Mubarak, testing the authority of the new government. The biggest protest was held in Qena province in southern Egypt, where some 5,000 people gathered around the office of governor Emad Mikhail to demand his resignation. Mikhail is one of two Christian governors appointed by the military generals who now rule Egypt and the protests in Qena have been going on for a week as Egyptians flex their newly found political muscle after Mubarak's ouster. Police brutality was one of the factors that ignited the mass protests that led to Mubarak's resignation in February. Protesters torched several police stations and former Interior Minister Habib el-Adli is now on trial for corruption and the violent crackdown on the uprising, which included the use of snipers and thugs against unarmed demonstrators. State media said Prime Minister Essam Sharaf would visit Qena soon to try to end the protests, which on Friday inspired thousands of Egyptians in the Mediterranean port city of Alexandria and the Nile Delta town of Dakahlia to take to the streets to demand their ex-police governors also resign. Islamists in the southern province of Qena, which has a large Christian population, had initially staged the protests, saying they wanted a Muslim governor. But the demonstrations have since widened to include Christians, who say they are not objecting to Mikhail's religion but that fact that he had worked closely with el-Adli. "We're not against him being a Christian. We want a civilian governor," said Abdul Hakim al-Sherif, a Muslim and an agricultural engineer. Christians make up some 10 percent of Egypt's 80 million people and Qena has seen its share of sectarian violence. In one high-profile case, Muslims killed six Coptic Christians in a drive-by shooting last year on Coptic Christmas Eve over the alleged rape of a Muslim girl. On Friday, the police and army tightened security around Qena's churches, but they remained on the sidelines of the anti-government protest, a stand unthinkable during Mubarak's authoritarian, 30-year rule. Mubarak was admitted to hospital the day he was ordered detained for questioning into allegations of graft and murder. He has denied any wrongdoing. On Friday, the public prosecutor said Mubarak would also be interrogated about a natural gas deal with Israel, whose terms opposition groups say is suspect. The former president was ordered detained for an additional 15 days for questioning on this arrangement. Israel gets 40 per cent of its natural gas from Egypt under the deal put in place after a 1979 peace accord. The new government has said it is reviewing the arrangement, and a statement from the prosecutor's office said the deal involved selling gas to Israel at prices way below market rates, which incurred losses worth over $714 million to the state. The former energy minister and five other senior energy officials were detained for questioning over the deal on Thursday.