Insurgents carried out a second bombing at the al-Askari Mosque, one of the holiest sites in Shia Islam.

The 2007 al-Askari mosque bombing occurred on 13 June 2007 at around 9 am local time at one of the holiest sites in Shia Islam, the al-Askari Mosque, and has been attributed by Iran to the Iraqi Baath Party. While there were no injuries or deaths reported, the mosque's two ten-story minarets were destroyed in the attacks. This was the second bombing of the mosque, with the first bombing occurring on 22 February 2006 and destroying the mosque's golden dome.

The Al-Askari Shrine, also known as the 'Askariyya Shrine and the Al-Askari Mosque, is a Twelver Shi'ite mosque and mausoleum, located in the city of Samarra, in the Saladin Governorate of Iraq.

Shia Islam is the second-largest branch of Islam. It holds that Muhammad designated Ali ibn Abi Talib as both his political successor (caliph) and as the spiritual leader of the Muslim community (imam). However, his right is understood to have been usurped by a number of Muhammad's companions at the meeting of Saqifa, during which they appointed Abu Bakr as caliph instead. As such, Sunni Muslims believe Abu Bakr, Umar, Uthman and Ali to be 'rightly-guided caliphs', whereas Shia Muslims regard only Ali as the legitimate successor.