Italian police have been ordered to tighten security at potential Catholic targets across the country as the leaders of the Catholic Church anxiously waited to see if a personal expression of regret by Pope Benedict would assuage Muslim fury over his remarks on Islam.
The controversy appeared to have claimed its first victim yesterday when gunmen killed an Italian nun and her bodyguard at the hospital where she worked in the Somalian capital, Mogadishu. A doctor said the nun had been shot four times in the back by two men with pistols.
The Vatican's spokesman, Father Federico Lombardi, said he hoped it was "an isolated event". He added: "We are worried about the consequences of this wave of hatred and hope it doesn't have grave consequences for the church around the world."
The pontiff, meanwhile, appeared to risk causing fresh controversy during his speech yesterday when he cited a passage from St Paul that risked being interpreted as hostile - not by Muslims, but by Jews. It described the crucifixion of Jesus as a "scandal for the Jews".
Jewish representatives yesterday expressed surprise at the latest incursion into sensitive territory. One, who asked not to be identified, said: "It does seem strange to come up with that particular quote at this particular time."
Rabbi Dr Jonathan Romain, a member of the board of the International Council of Christians and Jews, a group set up to combat religious prejudice, said: "He's really talking about veneration, not about the Jews. We can't alter the sayings of the past. But we can be careful about how we use them, especially in view of the religious offence that can be taken, even if never intended.
"The Pope has every right to quote his own holy texts, but it may be unwise in the current climate to choose those which relate to other faiths."