A man was killed on Sunday in Istanbul during mass in an Italian Catholic church by two masked assailants who opened fire. The Islamic State group claimed responsibility for the attack via the social network Telegram.

The victim, who attended the celebration, first identified by his initials C. T, was called Tuncer Cihan. The two attackers were arrested as they tried to flee, Interior Minister Ali Yerlikaya announced in the evening. About 40 people attended the mass, according to local officials, including the Polish consul general in Istanbul.