A leading international human rights group has accused Iraq's insurgent groups of committing war crimes.
An Iraqi woman mourns the death of her child - killed in a Baghdad suicide bombing
New York-based Human Rights Watch said rebels were breaking the laws of war by deliberately targeting civilians.
The group dismissed the insurgents' rationale for attacks on civilians.
The groups say that some civilians are legitimate targets because of their support for US-led forces operating in the country.
"There are no justifications for targeting civilians, in Iraq or anywhere else. Armed groups as well as governments must respect the laws of war," said Human Rights Watch Middle East director Sarah Whitson.
"It is time for political and religious leaders who support the insurgency to denounce the atrocities in public."
Human Rights Watch identifies al-Qaeda in Iraq, Ansar al-Sunna and the Islamic Army in Iraq as the groups responsible for the most indiscriminate violence.
Almost 300 people were killed in bombings across Iraq in September alone, with al-Qaeda in Iraq - thought to be led by Jordanian militant Abu Musab al-Zarqawi - claiming responsibility for some of the most deadly attacks.
Crimes Against Humanity
The report documents the assassination of government officials and politicians, as well as attacks on civilians at Shia mosques and Christian churches.
It also adds that the attacks on civilians by some groups are so widespread that they may constitute crimes against humanity.
Ultimately, the group blames the US-led invasion of Iraq for sparking the insurgency.
There is little agreement on the numbers of people involved in the Iraqi insurgency. Estimates vary from 30,000 to some 200,000 fighters - a figure cited by Iraqi intelligence in 2005.
Up to 3000 are thought be foreign jihadist fighters journeying to Iraq from Algeria, Syria, Yemen and Sudan and Saudi Arabia.