Insurgents killed an American soldier and wounded two others in a roadside bombing Tuesday in Baghdad.
That followed a brief mortar barrage in which at least three projectiles detonated about 9:15 p.m. Monday in central Baghdad, causing no damage or casualties, U.S. officials said. One hit a U.S. Army camp of the 2nd Armored Cavalry Regiment, the officials said.
Another soldier was killed Monday and one other wounded when their vehicle struck a land mine in Tikrit.
Insurgents fired five rocket-propelled grenades Tuesday at a hotel in Mosul which houses American troops but the projectiles caused no damage or casualties, the U.S. military said. A police station in the northern city of Mosul was struck overnight by a rocket-propelled grenade, the military said Tuesday. There were no casualties.
Elsewhere, witnesses said insurgents ambushed a U.S. patrol Tuesday with rocket-propelled grenades in the city of Khaldiyah, located west of Baghdad in the volatile "Sunni Triangle." There were no reports of casualties.
In other developments:
The dramatic increase in American hostile fire deaths this month was due to Sunday's downing of a CH-47 Chinook helicopter, which was carrying dozens of American soldiers on leave. Sixteen Americans died and another 20 were wounded.
The recent, bold attacks represent a major escalation in the campaign by a shadowy group of insurgents fighting to drive occupation forces out of Iraq. They also illustrated the vulnerability of American lines of communication to guerrilla ambushes and roadside bombings.
"The enemy in Iraq believes America will run, that's why they're willing to kill innocent civilians, relief workers, coalition troops," Mr. Bush told an audience in Birmingham, Ala. on Monday. "America will never run. America will do what is necessary to make our country more secure."
According to The Washington Post, the president took a broad view in his remarks to "reflect reality without getting bogged down in one day's headlines."
Until now, the U.S. military has believed that helicopters and transport planes provided a relatively safe mode of transport for ferrying troops and supplies around the country. That has been called into question by Sunday's attack on the Chinook. The military has cancelled daylight flights of the helicopter as a result.
Hundreds of SA-7 Strelas from the prewar Iraqi army are believed to have ended up in guerrilla hands along with a number of the advanced SA-18 Iglas equipped with special filters to defeat flares and other countermeasures deployed by U.S. aircraft.
The U.S. command has offered Iraqis $500 apiece for each portable missile turned in but has refused to say how many have been surrendered.
The Chinook attack was the largest U.S. death toll in any single action since the invasion of Iraq began March 20.
"Everybody was just laid out everywhere, and they were trying to search for most of the people that were left within the rubble," survivor Cpl. David Tennant told CBS News. "There was a lot of people screaming. I just remember waking up in the middle of the rubble, trying to escape, trying to get out of the burning metal."
Sixteen of the injured were flown by U.S. Air Force C-17 transport Monday to Ramstein Air Base in Germany and treated at the U.S. military's Landstuhl Regional Medical Center. Nine were admitted to the intensive care unit, including five in serious condition, said hospital spokeswoman Marie Shaw.
Four of the dead came from Colorado's Fort Carson, which has lost 25 soldiers in Iraq, its heaviest combat casualty toll since Vietnam.
Amy Leyenbecker, whose husband is also a soldier deployed to Iraq, spent Monday morning comforting Barbara Bucklew, whose husband died on the helicopter.
"It brings it all home," Leyenbecker said. "Before, it seemed so abstract. You think it's not going to hit someone I know."
As of Monday, 376 U.S. service members had died since the beginning of military operations in Iraq and 1,836 were wounded in hostile action. Non-hostile injured numbered 340.
On or since May 1, when Mr. Bush declared that major combat operations in Iraq had ended, 238 U.S. soldiers have died in Iraq, according to the latest Defense Department figures.
The British military has reported 50 deaths; Denmark, Spain and Ukraine reported one each.