Insurgents exploded a truck carrying chlorine gas canisters Wednesday — the second such "dirty" chemical attack in two days — while a U.S. official said ground fire apparently forced the downing of a Black Hawk helicopter. All nine aboard the aircraft were rescued.
Thunderous explosions reverberated through Baghdad after midnight as the security crackdown in the capital entered its second week.
The rash of spectacular insurgent attacks offer a sweeping narrative on evolving tactics by Sunni militants who have proved remarkably adaptable.
Military officials worry extremists may have recently gained more access to firepower such as shoulder-fired anti-aircraft rockets and heavy machine guns — and more expertise to use them. The Black Hawk would be at least the eighth U.S. helicopter to crash or be taken down by hostile fire in the past month.
The gas cloud in Baghdad, meanwhile, suggests possible new and coordinated strategies by bombers trying to unleash toxic — and potentially deadly — materials. "Terrorists are using dirty means," said Brig. Gen. Qassim Moussawi, an Iraqi military spokesman.
Lt. Col. Christopher Garver, a U.S. military spokesman, said initial reports indicated the chopper was brought down by "small arms fire and rocket-propelled grenades" north of Baghdad, but gave no further details. All nine aboard were taken away on a rescue helicopter, he said.
In Baghdad, a pickup truck carrying chlorine gas cylinders was blown apart, killing at least five people and sending more than 55 to hospitals gasping for breath and rubbing stinging eyes, police said.
On Tuesday, a bomb planted on a chlorine tanker left more than 150 villagers stricken north of the capital. More than 60 were still under medical care on Wednesday. Chlorine causes respiratory trouble and skin irritation in low levels and possible death with heavy exposure.
In Washington, two Pentagon officials said the tactic has been used at least three times since Jan. 28, when a truck carrying explosives and a chlorine tank blew up in Anbar province. More than a dozen people were reported killed.
A third Pentagon official said the United States has been concerned about Iraqi militants' ability to get weapons like chlorine bombs and use them effectively. But the official cautioned that chlorine bombs are just one threat on a long list of possible attacks that Iraqi fighters may try to carry out.
It was unclear whether the confluence of new insurgent tactics — attacking isolated combat posts, targeting helicopters more intensely and using chlorine bombs — was coincidental or in response to the U.S. troop increase.
In other developments:An Iraqi Sunni woman who leveled rape allegations against three members of the Shiite-dominated security forces was taken to a U.S.-run medical facility over the weekend, the chief U.S. military spokesman said Wednesday.Vice President Dick Cheney says the Iraq strategy advocated by Democratic leaders in Congress would "validate the al Qaeda strategy," and the top Democrat in the House of Representatives fired back that Cheney's remarks were out of bounds. House Speaker Nancy Pelosi said she had tried to complain about Cheney to President George W. Bush but could not reach him.A U.S. helicopter that crashed Wednesday north of Baghdad was shot down, the military said, reversing its initial statement that the chopper made a "hard landing." Military spokesman Lt. Col. Christopher Garver said all the occupants were safely evacuated by a second helicopter. British Prime Minister Tony Blair on Wednesday announced a new timetable for the withdrawal of British troops from Iraq, British media reported. About 1,600 are to leave the south of Iraq within "several months", and Blair said some of the remaining 5,500 soldiers could be pulled out before the end of the summerA suicide car bomber struck a police checkpoint Wednesday in the Shiite holy city of Najaf, killing at 13 people in the spiritual heartland of the militia factions led by radical cleric Muqtada al-Sadr. The Najaf blast hit while streets were filled with morning shoppers. At least two of the victims were police and the rest civilians, authorities said. It was the first major bombing in months in the city, which is heavily guarded by police and al-Sadr's powerful Mahdi Army militia.A second U.S. soldier has pleaded guilty to the gang rape and murder of a 14-year-old Iraqi girl and the killing of her family, saying he held the girl down and acted as a lookout while others took turns attacking her. Sgt. Paul E. Cortez, 24, pleaded guilty to four murders, rape and conspiracy to rape. Cortez said he conspired with three other soldiers — Pfc. Jesse V. Spielman, Spc. James P. Barker and Steven D. Green, who has been discharged — to rape Abeer Qassim al-Janabi. If the judge approves the deal, Cortez could avoid the death penalty.
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