A person has died after two masked gunmen attacked a church in Istanbul during Sunday services.
Two "masked assailants" attacked the Santa Maria Church in the Sariyer district at around 11.40am, Istanbul officials have said.
Turkish broadcaster T24 confirmed reports that one person died after being shot in the head during the attack.
They also reported that the attackers escaped, and others in the church threw themselves on the ground to protect themselves. No other injuries have been confirmed.
It is unclear what the motive behind the attack was and whether it is linked to any group.
An investigation has been opened and authorities are working to capture the pair involved, Turkey's Interior Minister Ali Yerlikaya has announced.
He said on X: "A large-scale investigation into the issue and efforts to catch the attackers have been initiated. We strongly condemn this vile attack."
Ekrem Imamoglu, mayor of Istanbul, also said: "We will never allow those who try to destroy our unity and peace by attacking the religious places of our city."
The shooting comes nearly four months after a suicide bombing in front of a government building in the Turkish capital Ankara.
Six people died in an explosion on Istiklal Caddesi, one of Istanbul's most popular streets and a tourist hotspot, in November 2022.
Turkey also suffered a string of deadly bombings between 2015 and 2017 by Islamic State and outlawed Kurdish groups.