Muslims also were called on to hold vigils outside Coptic churches as a show of solidarity, but some radical Islamic Web sites urged more attacks, publishing addresses in Egypt and Europe, the BBC reported Thursday.
Coptic Christians celebrate Christmas on Jan. 7, following the Julian calendar. Egypt's Coptic Christian minority makes up 10 percent of the country's 80 million people.
Twenty-one people died New Year's Day when a Coptic Christian church in Alexandra was bombed, setting off days of protests and riots by Christians who said the government encouraged discrimination and didn't do enough to protect Coptic Christians.
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