Islamist militants in Mali have attacked one of the most famous mosques in the historic city of Timbuktu, residents say.
Armed men broke down the door of the 15th-Century Sidi Yahia mosque, a resident told the BBC.
The Ansar Dine group, which is said to have links to al-Qaeda, seized control of the city earlier this year.
It has already destroyed several of the city's shrines, saying they contravene its strict interpretation of Islam.
Ansar Dine spokesman Sanda Ould Bamana told the BBC that his movement had now completed nearly 90% of its objective to destroy all mausoleums that are not in line with Islamic law.
He said Sharia did not allow the building of tombs bigger than 15cm (6 inches) above the ground.
The site of Sidi Yahia is one the three great mosques of Timbuktu, according to the UN cultural agency, Unesco.
The door which has been smashed had been left sealed as it led to the sacred tomb of saints.
The AFP news agency reports that some witnesses started crying when they saw the damage.