Egyptian border guards arrested 11 African refugees who were trying to cross illegally into Israel early Saturday, a security official said. Five of refugees were wounded during the confrontation, the official said. Guards opened fire on the refugees when they refused to surrender, wounding one of them in the knee before arresting them about 100 kilometers south of the Rafah Crossing in the central Sinai Peninsula, the official said. Four others were wounded after they tried to jump over barbed wire on borderline, said the official. The casualties were transferred to El Arish Hospital for treatment. The arrests came a day after an Egyptian border guard was killed near the Rafah terminal during a confrontation with smugglers who helped a larger group of refugees to cross into Israel, said the security official. Israel estimates that 2,800 people, mostly from Africa, have entered the country illegally through its border with Egypt in recent years searching for jobs. The number shot up over the summer, apparently as word spread of job opportunities in Israel. As many as 50 people arrived each day in June, according to the UN High Commissioner for Refugees.