A series of coordinated attacks struck Baghdad Tuesday, including two suicide car bombers and another vehicle that blew up near government sites. At least 127 were killed and hundreds wounded in the worst wave of violence in the capital in more than a month, authorities said.

A total of five attacks, which also included a suicide car bomb on a police patrol, showed the ability of insurgents to strike high-profile targets in the heart of Baghdad and marked the third time since August that government buildings were targeted with multiple blasts that killed more than 100 people.

SLIDESHOW: Baghdad Blasts

The bombings reinforced concerns about shortcomings in Iraqi security as U.S. forces plan their withdrawal, and parliament held an emergency session with many lawmakers demanding answers for apparent security lapses.

Iraq's military spokesman blamed the carnage on an alliance of Al Qaeda in Iraq and members of Saddam Hussein's banned Baath Party.

The U.S. military has sent some troops and forensic equipment to assist the Iraqis in the aftermath, said Army Master Sgt. Nicholas Conner, a military spokesman.

Overall violence has dropped sharply around Iraq in the past year, though insurgents have stepped up attacks at government sites in recent months. The bombings marked the most serious spate of violence in Baghdad since twin car bombs on Oct. 25 struck outside government offices, killing at least 155. In August, suicide bombers hit the finance and foreign ministries, killing more than 100.

Iraqi officials blamed the August and October attacks on Al Qaeda in Iraq and loyalists of the Baath Party — even bringing out three suspects on national television who gave what officials termed confessions.

There was no immediate claim of responsibility for Tuesday's attacks, though Al Qaeda in Iraq had said it was behind the last two massive bombings against government buildings in Baghdad in August and October.

But there are questions whether Iraq's leaders are trying to shift attention away from a possible resurgence of Sunni insurgents led by Al Qaeda in Iraq. A rise in insurgent power could be a serious blow to the government's credibility before national elections, which were set Tuesday for March 7 — a more than seven-week delay from the original mid-January date because of political bickering on the voting rules.

White House press secretary Robert Gibbs condemned the attacks, saying Iraqi leaders who recently passed an elections law were moving the country in the right direction and that "there are clearly those who are threatened by that."

United Nations Secretary-General Ban Ki-moon condemned the attack, calling the bloodshed "horrendous."

In a joint statement, U.S. Ambassador to Iraq Christopher Hill and Gen. Raymond Odierno, America's top commander in Iraq, called on Iraqis to unite against violence and pledged to assist the government "to bring to justice those individuals or groups responsible for such murder."

Again, Iraq's military spokesman, Maj. Gen. Qassim al-Moussawi, appeared Tuesday to spread the blame between Baath loyalists and Al Qaeda-linked extremists.

"The same hands that implemented the August and October attacks have carried out today's terrorist attacks against innocent civilians," he told The Associated Press.

Security forces worry the lead-up to the election date could bring an escalation in attacks seeking to discredit the pro-Western government of Prime Minister Nouri al-Maliki.

The core of the attacks hit central Baghdad with three blasts in the span of a few minutes.

The targets were the latest assaults directed at Iraqi authorities: near a compound with the Labor Ministry building, a court complex near the Iraqi-protected Green Zone and near the new site of the Finance Ministry after its previous building was destroyed in major attacks in August.

Police and hospital officials said at least 112 people were killed in those three attacks and at least 390 injured. Iraq's Health Ministry said as many as 513 people were injured. The officials spoke on condition of anonymity because they were not authorized to give information to media.

About an hour before the blasts, a suicide car bomber struck a police patrol in the mostly Sunni district of Dora in southern Baghdad, killing at least three policemen and 12 civilians and injuring five people, said a police official, who spoke on condition of anonymity because he was not authorized to speak to media.

In eastern Baghdad, a roadside bomb exploded near the Technology University in eastern Baghdad, missing a passing police patrol but killing one civilian passer-by and wounding four others, Baghdad police said.

Iraqi police said at least two of the Baghdad blasts were suicide bombers — one driving a bomb-rigged ambulance heading for the Finance Ministry and the other plowing through a barrier near the Appeals Court building and exploding the car as guards opened fire.

"The (court) building is severely damaged," said the spokesman of Iraq's Supreme Judicial Council, Abdul-Sattar.

The third explosion may have been bomb-rigged cars detonated by a timer or a trigger.

"What crime have we committed? Children and women were buried under debris. Why did they (Iraqi troops) let this car bomb pass!" cried Ahmed Jabbar as he staggered through the debris near the new Finance Ministry building — an area where all cars pass through checkpoints manned by Iraqi forces.

A Kurdish parliament member, Mohammed Shareef Ahmed, was among several lawmakers demanding a full-scale inquiry.

"The parliament today is so angry toward the security services which we feel have failed to prevent these attacks ... We all feel — and all the world feels — that the Iraqi people are fed up of sufferings and something should be done to stop this."

The blast tore through a nearby market and toppled at least one building nearby. Rescue teams — some using construction cranes — tried to pull away the rubble to look for survivors.

The breakdown of casualties among the sites was not immediately clear, but the most serious bloodshed had been reported outside the new Finance Ministry building and the court complex, where at least one building was almost completely leveled.

Rescue workers climbed through twisted steel bars and crushed concrete at the flattened court building. Dozens of cars and trucks were burned and crushed.

Firefighters pulled survivors from behind huge slabs of toppled concrete. U.S. soldiers helped provide security and assisted the Iraqis with the collection of evidence from the rubble.