4 Separate Iraq Blasts Kill At Least 23

(CBS/AP) A female suicide bomber blew herself up near an entrance to the U.S.-protected Green Zone and a bomb tore through a minibus carrying Iraqi government employees in separate attacks on Monday that killed at least 20 people, Iraqi officials said.

A third attack on an Iraqi police patrol in Baghdad killed two civilians, police said.

The violence came as Iraqi lawmakers prepared for a vote Wednesday on a security pact with the United States that would enable American forces to stay in Iraq for up to three more years under strict Iraqi oversight.

In the first attack, a bomb attached to a bus used by the Trade Ministry to ferry employees to work exploded shortly before 8 a.m. in eastern Baghdad, police and hospital officials said on condition of anonymity because they were not authorized to speak to the media.

Thirteen ministry employees were killed and three were wounded, according to an official with the state-owned Iraqi shopping centers company who also spoke on condition of anonymity. The company is part of the Trade Ministry.

The rush-hour attack occurred in a Shiite area and the injured were taken to Kindi hospital in Baghdad.

The U.S. military said 14 people were killed and four were injured in the 7:20 a.m. blast on the minibus. It said American soldiers assisted Iraqi police in securing the area and treating casualties.

About 45 minutes later, a female suicide bomber blew herself up as she stood in line to be searched at a checkpoint near the Green Zone in central Baghdad, killing seven people and wounding 13, according to an Interior Ministry official who declined to give his name.

The U.S. military said the bombing near the Green Zone occurred between 8:30 a.m. and 9 a.m. and killed two Iraqi army members and three civilians. One civilian was injured, it said.

The Green Zone houses the U.S. Embassy and the Iraqi government headquarters.

In a third attack, a roadside bomb targeted a police patrol around 10:30 a.m. near Technology University in eastern Baghdad, killing two civilians and wounding four other people, an Iraqi police officer and an official at Ibn al-Nafis hospital said on condition of anonymity. Two police officers were among the injured.

Meanwhile, the U.S. military is rushing to build criminal cases against some 5,000 detainees it deems dangerous - including suspected members of al Qaeda in Iraq - because the proposed security pact with Iraq would end its right to hold prisoners without charge.

The agreement, which is to be voted on by Iraqi lawmakers Wednesday, is primarily intended to set a timetable calling for American troops to leave Iraq by the end of 2011. But it also calls for control of security matters to shift to Iraqi authorities.

If passed, the deal would mean U.S. troops could no longer hold people without charge as they have since the 2003 invasion that ousted Saddam Hussein. Beginning Jan. 1, all detentions would have to be based on evidence, and the U.S. would have to prosecute prisoners in Iraqi courts or let them go.

"At the end of the day, if there's not enough facts to justify a court case, then we'll have to release," said Brig. Gen. David Quantock, the commander of the U.S. detention system in Iraq.

The Americans have evidence against only "a few hundred" of the most dangerous detainees, Quantock said, leaving open the possibility that thousands could find themselves back on Iraq's streets soon.

"We have a lot of work to do," he said.

Part of the challenge stems from differences between the U.S. and Iraqi legal systems. In the United States, forensic evidence is widely used in the courts. Not so in Iraq

"We've got a number of guys right now that are covered in TNT (explosive residue). However, that's not admissible in Iraqi court," Quantock said. "What wins the day in Iraqi courts today is two eyewitness statements or a confession."

The U.S. is training Iraqi forensic specialists and pushing to make such evidence more acceptable in court. Iraqi judges are slowly bending, but it is expected to take time before forensic evidence wins wide approval.

The transition comes amid a marked improvement in security that has boosted the confidence of Iraq's government and allowed security-based detention to give way to a civilian justice system. It would also mark a major step toward shutting down a detention system that was tainted by the scandal at Abu Ghraib prison outside Baghdad, where U.S. guards abused detainees.

U.S. forces are holding around 16,500 detainees in all. The largest facility, with some 12,900 prisoners, is at Camp Bucca near the city of Basra, some 340 miles southeast of Baghdad.

Camp Cropper, on the sprawling U.S. base near Baghdad International Airport outside the capital, serves as the system's logistical headquarters and houses some 2,000 prisoners. All detainees entering and leaving U.S. custody pass through Cropper.

On a recent trip to the base, Associated Press journalists saw detainees dressed in yellow pants and shirts or traditional robes chatting outside low-slung, peach-colored barracks. Some ritually washed their hands and feet before afternoon prayers, while others set out laundry to dry in the midday sun. Guards kept watch from towers looming over a double row of barbed-wire fences.

The vast majority of those in U.S. custody are not considered dangerous, so the military is focusing its legal efforts on the 5,000 it deems a threat.

Iraq's government will receive the names and other details of those in U.S. custody so it can issue arrest warrants for some of them. Quantock said he is confident that either the U.S. or Iraqi government will muster enough evidence to keep many of the most dangerous individuals behind bars.

But releasing the other 11,000 prisoners, who are not considered a serious threat, also poses a challenge.

The security agreement before Iraq's parliament stipulates that detainees be let go "in a safe and orderly manner."

U.S. and Iraqi officials are mindful of the dangers posed by dumping thousands of suspected insurgents, even if minor players, into communities already grappling with high unemployment.

"The fact that they are going back to their cities and homes might complicate the security situation," said Haider al-Ibadi, a Shiite lawmaker with close ties to Prime Minister Nouri al-Maliki. "But we can do nothing to stop this because the authorities cannot arrest or keep any person in custody without evidence."

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