In February 2006, the Salafi jihadist organization Tanzim Qaidat al-Jihad fi Bilad al-Rafidayn (also known as Al-Qaeda in Iraq) bombed one of the holiest sites in Shi'a Islam - the al-Askari Mosque in Samarra. This set off a wave of Shi'a reprisals against Sunnis followed by Sunni counterattacks. The conflict escalated over the next several months until by 2007, the National Intelligence Estimate described the situation as having elements of a civil war.