The rising toll among Americans pointed to a potentially deadly trend: More troops exposed to more dangers as they try to reclaim control of Baghdad under the joint security plan being implemented by U.S. and Iraqi forces.
Bombings and shootings nationwide Monday killed at least 102 people.
After sunset, there was no let up. Thunderous explosions rocked central Baghdad - apparently from rockets fired toward the U.S.-controlled Green Zone. Warning sirens sounded in the heavily protected district, and witnesses saw smoke rising from the area. The U.S. military said it had no immediate information about damage or casualties.
The rockets appeared to come from a part of eastern Baghdad where Shiite militiamen operate. But the barrage suggested that Shiite gangs could be regrouping after falling back when the Baghdad security sweeps got under way.
Five U.S. military deaths were announced Monday. All but one occurred over the weekend in Iraq's capital, where a nearly 11-week security crackdown has put thousands of additional American soldiers on the streets - making them targets for both Shiite and Sunni extremists.
In a statement, the U.S. command said three American soldiers and an Iraqi interpreter were killed by a roadside bomb Sunday in eastern Baghdad. Another U.S. soldier was killed Saturday by small arms fire in the same area, the statement said.
A Marine died in combat Sunday in Anbar province, a Sunni insurgent stronghold west of the capital, the military said.
The 104 deaths among American service members in Iraq in April were eight fewer than December's toll of 112, and the sixth-highest figure for a single month since the war started in March 2003.
Last week, the top U.S. commander in Iraq, Gen. David Petraeus, warned in Washington that "there is the very real possibility" of intense combat in the coming months and "therefore, there could be more casualties."
President Bush has committed some 30,000 extra American troops to the security operation in Baghdad, but he is facing legislation by the Democratic-led Congress calling for U.S. troops to begin withdrawing from Iraq by Oct. 1. Bush has promised to veto the measure.
While American casualties are rising, U.S. officials say the Baghdad crackdown has reduced civilian deaths in the capital since the security operation was launched Feb. 14. But figures compiled by The Associated Press from police reports show a rise in civilian casualties outside the capital, where extremists took refuge to avoid the Baghdad operation. Police said 32 people were killed and 63 wounded when the suicide bomber struck the Shiite funeral in Khalis, about 50 miles north of Baghdad. The bomber walked into a tent filled with mourners and detonated a belt of explosives hidden beneath his clothes, police said. Attacks on funeral gatherings are not uncommon. Suicide attacks are the hallmark of Sunni religious extremists, notably al-Qaida in Iraq. "I saw panicked people running from outside the tent," said a mobile telephone dealer who was walking toward the tent when the bomber struck. "It was the most horrible scene I ever witnessed. I was shocked that somebody could commit this crime against people who were honoring a dead person." The witness, who refused to give his name out of fears for his safety, said the bomber timed the attack for early evening, when large numbers of mourners usually arrive for food provided by the family of the deceased. Officials said the funeral was for a Shiite man who died of natural causes, but has about 20 relatives in the army and police. Four days ago, a suicide car bomber killed 10 Iraqi soldiers at a checkpoint in Khalis, a mostly Shiite town in a predominantly Sunni area. Al-Qaida in Iraq claimed responsibility. Elsewhere, a tanker truck exploded near a restaurant just west of Ramadi, the capital of Anbar province, killing four people and wounding six, police said. The attack occurred in an area where U.S.-backed Sunni sheiks and tribal leaders have begun turning against al-Qaida, forming the Anbar Salvation Council to drive religious extremists and foreign fighters from their area. That has helped curb violence in Ramadi, once the most dangerous city in Iraq, but has triggered clashes for control of the vast desert area that borders Syria, Saudi Arabia and Jordan. In a Web posting Monday, an al-Qaida front organization - the Islamic State in Iraq - announced it was preparing a "long-term war of attrition" in Anbar against the Americans and the U.S.-backed Sunni sheiks. "The Marines do not confront the militants face-to-face, but they hide behind thieves and highway robbers," the group said, referring to the tribal alliance. "The mujahedeen are ongoing in their fights against the enemies of God." At least 66 other people were killed or found dead nationwide Monday, police reported. They included 27 bullet-riddled bodies found in Baghdad, apparent victims of sectarian death squads. Iraq's Sunni Arab Vice President Tariq al-Hashemi discussed threats by Sunni ministers to leave the Shiite-dominated government during a weekend telephone conversation with Bush, the vice president's office said Monday. The White House confirmed that Bush called al-Hashemi on Sunday to discuss "the current situation in Iraq" and "the importance of additional steps in the reconciliation process." In a statement on his Web site, al-Hashemi said the call was made after his Iraqi Accordance Front threatened to quit the Cabinet. Al-Hashemi is one of three leaders of the main Sunni bloc in parliament. It holds 44 of the 275 seats in parliament and five Cabinet posts, including the Defense Ministry. Bush and al-Hashemi "spoke frankly about the stumbling political process and ways of getting out of the current dilemma," the vice president's statement said. "It seems that the (Accordance) Front has lost hope for a change in the current situation." The Front's departure from the Cabinet could plunge Iraq into a major political crisis because it would mean the end of the fragile unity government of Shiites, Sunnis and Kurds. AP-CS-04-30-07 1910EDT