* Attacks at end of holy month of Ramadan kill dozens
* Sectarian violence escalates in Iraq
* U.S. repeats offer of $10 mln for al Qaeda in Iraq chief
By Sylvia Westall
BAGHDAD, Aug 11 (Reuters) - The United States has condemned the latest bombings in Baghdad which killed dozens of people, saying attackers who targetted civilians during celebrations marking the end of Ramadan were "enemies of Islam".
Car bombs ripped through markets, shopping streets and parks late on Saturday as Iraqis were out celebrating Eid, the end of the Muslim fasting month, killing 57 and wounding more than 150.
Eighteen months since the last U.S. troops withdrew, Sunni Islamist militants have been regaining momentum in their insurgency against Iraq's Shi'ite-led government.
The civil war in neighbouring Syria has aggravated sectarian tensions further and Iraq's Interior Ministry has said it is facing an "open war".
"The United States condemns in the strongest possible terms the cowardly attacks today in Baghdad," the State Department said in a statement.
"The terrorists who committed these acts are enemies of Islam and a shared enemy of the United States, Iraq, and the international community," it said.
It said the United States would work closely with the Iraqi government to confront al Qaeda and discuss this during a visit of Foreign Minister Hoshiyar Zebari next week to Washington.
This has been one of the deadliest Ramadan months in years, with bomb attacks killing scores of people. The latest bombings were similar to attacks in Baghdad on Tuesday in which 50 died.
More than 1,000 Iraqis were killed in July, the highest monthly death toll since 2008, according to the United Nations.
Elsewhere in Iraq on Saturday, similar explosions hit bustling streets and a mosque. The attacks targeted mainly Shi'ite districts and the renewed violence has raised fears Iraq could relapse into the severe sectarian bloodshed of 2006-2007.
"This carnage reflects the inhuman character of its perpetrators," United Nations envoy to Iraq Gyorgy Busztin said in a statement.
"All honest Iraqis should unite to put an end to this murderous violence that aims to push the country into sectarian strife," he said.
The State Department said Saturday's attacks bore the signs of al Qaeda's Iraqi (AQI) branch. It reiterated a $10 million reward for information leading to the killing or capture of Abu Bakr al-Baghdadi, the AQI leader.
Last month al Qaeda claimed responsibility for simultaneous raids on two Iraqi prisons and said more than 500 inmates had escaped in the operation, one of its most brazen in Iraq.
The reward for Baghdadi is second only to information leading to Ayman al-Zawahri, the chief of al Qaeda's network, the State Department said. (Editing by Louise Ireland)