 Complete the following phrase:  An insurgency against the US-led coalition-rule of Iraq began in summer 2003 within elements of the former Iraqi secret police and army, who formed guerrilla units. In fall 2003, self-entitled jihadist groups began targeting coalition forces. Various Sunni militias were created in 2003, for example Jamaat al-Tawhid wal-Jihad led by Abu Musab al-Zarqawi. The insurgency included intense inter-ethnic violence between Sunnis and Shias. The 