BAGHDAD - Iraq's Western-backed government, facing intense pressure to address security after suicide bombs killed 127 on Tuesday, ordered a shake-up yesterday in the country's military leadership.

The angry mood that led Prime Minister Nouri al-Maliki to replace Baghdad's top military commander revealed a stark psychological shift among Iraqis who once accepted such violence as routine but who are now demanding someone pay a political price.

Maliki appealed for Iraqis to be patient as he signaled that more changes might be ahead for security officials. The prime minister was expected to attend a special parliamentary session today, where lawmakers demanded his security ministers answer for lapses that allowed for the attacks.

"I call on the Iraqi people for more patience and steadfastness," Maliki said in a televised address.

It was unclear whether the replacement of Lt. Gen. Abboud Qanbar would quiet outraged lawmakers, who are questioning how suicide bombers managed to launch multiple attacks Tuesday in heavily guarded central Baghdad. The blasts wounded more than 500.

Much of Maliki's appeal was aimed at calming anger that has united Iraq's ethnic and sectarian rivals - from Kurd to Arab, Shiite to Sunni - with their calls on Iraq's interior and defense ministers to resign.

"They have proved failures," said Saadi al-Barzanji, a Kurdish lawmaker.

Even the group that Iraq has accused of masterminding this week's bombings, as well as two previous major attacks, called on security officials to step down. "He who cannot ensure security for Iraqis should leave," Baath Party spokesman Khudair al-Murshidi said in an interview. Murshidi has denied that loyalists of Saddam Hussein's Baath Party were behind any of the attacks.

Top security officials have twice failed to appear after being called before lawmakers. Those request followed suicide bombings against government buildings Aug. 19 and Oct. 25. More than 250 were killed in the earlier attacks.

Parliament Speaker Ayad al-Samarrie on Tuesday again called on the ministers and others to appear before legislators. Yesterday, Interior Minister Jawad al-Bolani said he would attend the session only if it was not held behind closed doors, according to a statement released by his office. It was not clear whether his demand was met or whether other officials would attend. Security matters have typically been discussed in parliament in closed session.

During Maliki's address on state television, he said Iraq's security strategies would be reviewed and possible personnel changes made. He stopped short of saying whether any of his ministers would be held responsible.

Maliki also appointed Lt. Gen. Ahmed Hashim Ouda late yesterday to head Baghdad's military operations, according to state television. Ouda has been a close political ally of Maliki's and belongs to his Dawa Party.

The prime minister previously has not asked any of his top security advisers to step down, but he now may have little choice this time. Maliki has been running for reelection on a platform of improved security, and a lack of response could cost the prime minister and his party votes.

The United States has refrained from commenting publicly about the security lapses, instead warning of a possible rise in violence aimed at destabilizing the government ahead of the March 7 parliamentary elections. The top American commander in Iraq, Gen. Raymond Odierno, has said he will keep the bulk of the 120,000 U.S. troops in place until after the election.

There have been no claims of responsibility for the latest bombings, though the U.S. military has said high-profile vehicle bombs and simultaneous suicide bombings are the hallmarks of al-Qaeda.

In his address, Maliki also called on neighbors to do more to prevent insurgent attacks in Iraq, an apparent reference to Syria. Relations between the two countries soured after Baghdad accused Syria of harboring senior Baathists who masterminded the attacks in August and October. Syria denies it.