At least 18 children died in a fire that killed dozens of worshippers gathered for Sunday morning mass at a church in Giza, greater Cairo, according to hospital documents seen by CNN, The toll stands at 41 dead and 14 injured, Egypt’s Coptic Church said in a statement, citing health officials. The hospital documents show the children were ages 3 to 16. The fire started at about 9 a.m. local time due to an electrical failure in an air conditioning unit on the church’s second floor, Egypt’s Interior Ministry said. The small church is located in the highly populated Imbaba neighborhood. Most of the deaths and injuries were caused by smoke inside church classrooms after the electrical failure, the ministry said in a Facebook post. At least two officers and three civil protection service members were injured responding to the fire, the ministry said. Church officials also believe the fire was accidental, said Coptic Church spokesperson Archpriest Moussa Ibrahim, adding a priest was among those killed.