An Egyptian security official says one man was killed and three others injured when Muslims and Christians clashed over the expansion of a monastery south of Cairo. The two sides exchanged fire Saturday before police intervened and made several arrests near the Minya, 210 kilometers south of the capital. In addition to the deceased man, who was a Muslim, three Christians were injured. The official, who spoke on condition of anonymity because he was not authorized to speak to the press, said that authorities have requested reinforcements to contain the situation. The battle erupted when local Muslims claimed the expansion of a monastery was being carried out illegally on state property. Christians make up 10 percent of Egypt's 76.5 million people.