The killings significantly picked up after Iraqi security forces launched a heavy-handed crackdown on a Sunni protest camp in the northern town of Hawija on April 23. A ferocious backlash followed the raid, with deadly bomb attacks and sporadic gunbattles between insurgents and soldiers this time members of the Iraqi security forces rather than U.S. troops.
The U.N. Mission in Iraq said 1,057 Iraqis were killed and 2,326 wounded in July, the highest toll since June 2008 when 975 people were killed.
The increase was particularly troubling because the numbers had begun declining five years ago following a series of U.S.-led offensives and a Sunni revolt against al-Qaida in Iraq.
"We haven't seen such numbers in more than five years, when the blind rage of sectarian strife that inflicted such deep wounds upon this country was finally abating. I reiterate my urgent call on Iraq's political leaders to take immediate and decisive action to stop the senseless bloodshed, and to prevent these dark days from returning," acting U.N. envoy to Iraq, Gyorgy Busztin, said in a statement.
The U.N. said that 928 of those killed in July were civilians and 129 were Iraqi security forces.
In all, 4,137 civilians have been killed, mostly in Baghdad, and 9,865 wounded so far this year, according to the statement. That was up from 1,684 killed in the January-July period last year.
Al-Qaida in Iraq has claimed responsibility for many of the suicide attacks and car bombings in recent days as it seeks to stoke sectarian hatred and undermine Iraq's Shiite-led government. Much of the violence is targeting Shiites who have held the reins of power since Saddam's Sunni-dominated regime was ousted.
An interior ministry official attributed the recent uptick in the death toll figures to a change in tactics by insurgents who are now trying to attack crowded, soft civilian targets such as cafes, mosques and markets in order to kill as many people as possible.
The official said that one of the new insurgents' tactics is to attack one target with two car bombs or two suicide bombers, instead of single bombing, in order to have higher causalities.
"This new tactic shows that the armed groups now have more resources, more car bombs, more bombers and more support with greater freedom to move and select target" said the official, who spoke on condition of anonymity because he is not authorized to talk to media.
U.N. Secretary-General Ban Ki-moon last month described the scale of violence as alarming and warned that the increasingly sectarian-charged civil war raging in neighboring Syria is affecting Iraq's own political stability.
Although Iraq is officially neutral in the conflict, U.S. officials charge that it continues to allow flights suspected of carrying Iranian arms to transit its airspace. Iraqi officials have carried out some spot checks of Iranian planes and say they've found nothing. Iraqi fighters are meanwhile traveling to fight in Syria, with Shiites fighting alongside President Bashar Assad's forces and Iraq's al-Qaida arm, now known as the Islamic State of Iraq and the Levant, siding with the mostly Sunni rebels.
"Iraq has become part of the ongoing regional struggle between regional powers such as Iran, Saudi Arabia and Turkey," Baghdad-based political analyst Hadi Jalo said. "The growing power of al-Qaida-linked extremist groups in Syria is having a devastating impact on the Iraqi situation. Now the Islamic fighters have much more freedom to move across the Iraqi-Syrian borders in order to launch attacks in both countries and these groups are helping each other because they believe that they are united by one goal, which is to establish an Islamic state in Iraq and Syria and their joint aim is to destabilize both countries. "
Iraqis also blamed the government for failing to provide capable security forces to protect the people.
"We are witnessing the return of the dark days of the civil war that took place in 2006-2007 and the country is returning to square one where the armed groups have the upper hand in the country," said Riyadh Hussein, a government employee from eastern Baghdad. "We are moving in a vicious circle full of political feuds and security failures.
"The security forces have no experience or capability to stop al-Qaida, while on the other hand the armed groups are getting stronger, both in quality and quantity," he added.
The violence continued Thursday. Three policemen were killed when a roadside bomb exploded by a police patrol near the northern city of Mosul shortly before sunset, a security official said.
A hospital official confirmed the death toll. The two officials spoke on condition of anonymity because they are not authorized to talk to journalists.
Associated Press writer Kim Gamel in Cairo contributed to this report.