An explosion outside a church in the north Egyptian city of Alexandria has killed seven people and injured 24, the interior ministry says. The blast, apparently caused by a car bomb, hit people as they left a new year's service at the al-Qidiseen church shortly after midnight. Afterwards, angry worshippers reportedly threw stones at the police and targeted a nearby mosque. Sectarian tensions have recently been on the rise in Egypt. The mayor of Alexandria, Gen Adel Labib, said on Egyptian TV that there had been threats of attacks on churches, though he tried to play down any possible sectarian motive for Saturday's bombing. Following the blast, witnesses said Christians were chanting: "We sacrifice our souls and blood for the Cross." Protesters went into a mosque, throwing books out onto the street, the Associated Press news agency reported. There was a burnt-out car in front of the church, witnesses said. Officials said they were still investigating whether the car had been rigged with explosives. Sectarian violence Christians from the Coptic Orthodox Church make up about 10% of Egypt's predominantly Muslim population. The rise of political Islam and the failure of the government to address Coptic claims of discrimination have fuelled divisions, analysts say. Al-Qaeda in Iraq has also been conducting a campaign against Christians following the reported conversion to Islam by two Egyptian Christian women in order to divorce their husbands. Alexandria, Egypt's second-largest city with a population of about four million, has seen sectarian violence in the past. In 2006, there were days of clashes between Copts and Muslims after a Copt was stabbed to death during a knife attack on three of the city's churches. Source: BBC