Two U.S. soldiers killed in crash
Helicopter downed by small arms fire in Iraq
This OH-58 helicopter is similar to the one that was shot down Thursday near Baquba, Iraq.
U.S. Marines launch a major offensive in Haditha.
Several Islamist militant Web sites report al-Zarqawi wounded.
Concern grows in Iraq over Sunni vs. Shiite violence.
BAGHDAD, Iraq (CNN) -- Two U.S. soldiers were killed when their helicopter went down near Baquba, 40 miles northeast of Baghdad, the U.S. military said.
Their OH-58 Kiowa chopper was flying alongside a second helicopter when they received small arms fire from the ground. The second chopper managed to get to a coalition base safely, but was damaged, the military said.
The shootdown came on the day Iraqi ministers announced a new security plan for Baghdad to fight the insurgency.
And there were conflicting reports on whether insurgent leader Abu Musab al-Zarqawi was wounded.
"We are not quite sure if he is alive or dead," said Interior Minister Baqir Jabbur, citing information on al-Zarqawi's injuries the government received several days ago.
But Iraqi Prime Minister Ibrahim al-Jaafari later said the government didn't have anything accurate on al-Zarqawi's status.
Al-Zarqawi, the most-wanted man in Iraq, is blamed for bombings and kidnappings throughout the country. The United States is offering a $25 million reward for information leading to his capture.
Following a Baghdad news conference, Jabbur confirmed to CNN that al-Zarqawi had been hurt: "Yes, it is true he has been wounded."
Several Islamist Web sites reported this week that al-Zarqawi had been wounded and asked supporters to offer prayers for the militant.
In an analysis of one posting, CNN's senior editor for Arab affairs said the author "doesn't go into the seriousness of the injuries."
"If indeed there is an injury, the injury is serious enough for the group to be inclined to announce it publicly so that in case of death, it won't be a total shock," Octavia Nasr said earlier this week.
The message "could be just a prelude to announcing something even more serious," she said. (Full story)
Last year al-Zarqawi pledged his allegiance to Osama bin Laden, who later praised the insurgent's work against American troops in Iraq.
At the Pentagon, U.S. Army Brig. Gen. Carter Ham said Thursday that he cannot corroborate reports about the insurgent leader's possible injuries and sought to downplay such a development.
"While al-Zarqawi is an important character, his organization is bigger than just one guy," Ham said. "His demise, whether he is captured, which would be preferable, or if he is killed or wounded, that would not cause al Qaeda in Iraq to cease to function."
40,000 troops to patrol capital
At Thursday's briefing, Jabbur and Defense Minister Sadoun al-Dulaimi also announced a plan to bolster security in Baghdad and combat the insurgency.
More than 40,000 security personnel will be stationed in the capital of 6 million people.
"We will not allow murderers and terrorists and extremists to shed Iraqi blood," al-Dulaimi said. "We will stand up to them."
Beginning next week, Baghdad will be divided into quadrants for soldiers and police to patrol, the ministers said. Authorities will set up security cordons and checkpoints throughout the city, the officials said, adding that raids will be conducted when required.
Anti-insurgent operations also are planned for other cities in Iraq, which remains under a state of emergency except for the Kurdish region in the north.
Jabbur said mosques that harbor terrorists and weapons caches will be raided. Al-Dulaimi issued a ban on such raids last week.
The U.S. military said it's nabbed 21 suspected insurgents in Baghdad, Mosul and Tal Afar.
Among the 11 arrested during a raid in Baghdad early Thursday were two men described as "specifically targeted suspects."
The military identified one as a police officer who served under Saddam Hussein and is "thought to be involved in terror cells."
The military says the suspected insurgent scouts roads "for coalition convoys, then initiates and participates in attacks against them."
The other detainee "is thought to be involved with a terror cell that assassinates or kidnaps Iraqis" who work with the army, police or coalition forces, the military said.
Two raids around Mosul brought in nine more suspected terrorists; the remaining person was captured in Tal Afar.
Also Thursday, Multi-National Forces from Task Force Freedom said soldiers took into custody six suspected terrorists south of Mosul and one in a raid in Tal Afar.
Another raid in western Mosul netted three suspected terrorists, the military said.
Meanwhile, insurgents killed a local police chief and two police officers at Mosul University, authorities said. Miklif Mussa was the police chief of nearby al Sharqat.
Other developmentsThe U.S. military said authorities are searching for three detainees who escaped from Abu Ghraib prison before sunrise Thursday. Forces discovered "two holes in the compound fence," a military statement said.At least 10 people died in a series of attacks Thursday in the Iraqi capital, police said. Gunmen killed six people in three separate attacks -- including a college professor and three bodyguards; a Shiite restaurant owner; and Thamir Ni'ma Ghaydan, an Industry Ministry official. A member of the Shiite party al-Dawa, Fakri Abed al-Amri, was knifed to death, and a suicide bomb in a taxi killed two police officers and a civilian and wounded six others, police said. An Iraqi child died Thursday during a shootout between insurgents and coalition forces in northern Iraq's Tal Afar, the U.S. military said. The military said insurgents used the child as a shield.U.S. and Iraqi forces involved in an offensive in the western city of Haditha have detained five suspected insurgents, the U.S. Marines said Thursday. One Marine died and at least 10 insurgents were killed Wednesday, the first day of Operation New Market. Since the start of the war, 1,649 U.S. forces have died in Iraq.
CNN's Jane Arraf, Ryan Chilcote, Arwa Damon, Enes Dulami, David Ensor, Kianne Sadeq and Jamie McIntyre contributed to this report.