Isis has destroyed a 2,000-year-old ancient structure near the Iraqi city of Mosul.
The Mashqi Gate, also known as the Gate of God, was one of a number of grand gates which guarded the ancient Assyrian city of Nineveh.
Referenced in the Bible, Nineveh dates to the 7th century BC and was once the largest city in the world.
The act is the latest incident in a campaign of cultural vandalism Isis has undertaken in territory it controls.
A source at the British Institute for the Study of Iraq confirmed to The Independent that the gate had been attacked.
Activists in Mosul told Kurdish news outlet ARA News the Islamist militants had used military equipment to destroy the gate.
The destruction of the Mashqi Gate is the latest in a series of historical artefacts to be destroyed in Isis-held territory by the militant group, who view many relics predating Islam as sacrilegious.