Yerlikaya, who condemned the attack, said it took place around 0840 GMT at the Italian Santa Maria Catholic Church in the Sariyer district.

"C.T., who was among those participating in the service, was the target of a gun attack by two masked individuals and sadly lost his life," the minister said on social media platform X, referring to the initials of the victim.

Turkish officials tend to not use the full names of victims or perpetrators of attacks.

It was not immediately clear why the victim was targeted. Footage from the church showed several police cars and an ambulance outside the building.

(Reporting by Tuvan Gumrukcu; Editing by Bernadette Baum)