Baghdad, Iraq ? Three masked gunmen in a speeding Opel assassinated a second lawyer in the Saddam Hussein trial Tuesday, casting doubt on Iraq’s ability to try the case and leading a prominent war crimes prosecutor to urge moving the proceedings to another Arab country.

Adel al-Zubeidi, lawyer for former Vice President Taha Yassin Ramadan, died when bullets were sprayed at his car in a largely Sunni Arab neighborhood of western Baghdad. The shots also wounded Thamir al-Khuzaie, attorney for another co-defendant, Saddam’s half brother Barazan Ibrahim.

The brazen daylight attack on a major avenue came three weeks after the kidnap-slaying of another defense lawyer, Saadoun al-Janabi. His body was found Oct. 20, one day after the trial’s opening session, where he represented Awad al-Bandar, a former official in Saddam’s Baath Party.

No group claimed responsibility for the killings. An Iraqi government spokesman pointed to Saddam loyalists for the latest attack, while the dictator’s lawyer blamed the Shiite-dominated government.

Saddam Hussein speaks to Judge Rizgar Mohammed Amin, unseen, as his trial begins in a heavily fortified courthouse in Baghdad's Green Zone in this Oct. 19 file photo. A lawyer for a co-defendant in Saddam Hussein's trial was shot to death and another lawyer was wounded Tuesday in Baghdad, a member of the defense team said.

Regardless of who was responsible, the killing of another defense lawyer reinforced grave misgivings among human rights groups and international lawyers about holding the trial in a country gripped by a brutal insurgency – much of it led by the defendants’ supporters in the Sunni Arab minority.

“I don’t understand how you can have a fair trial in this atmosphere of insecurity, with bombs going off,” said Richard Goldstone, the first prosecutor at the U.N. tribunal for war crimes in the former Yugoslavia and one of the world’s most prominent jurists.

He told The Associated Press by telephone that Iraq’s government should consider shifting the trial to an Arab country “where there is security.”

Laith Kubba, spokesman for Prime Minister Ibrahim al-Jaafari, brushed aside that idea and insisted the next session would proceed in Baghdad as planned Nov. 28. State Department spokesman Adam Ereli said Washington would support Iraq as it proceeds with the trial.

Both the Iraqi government and the United States have long insisted the trial be held in Iraq before an Iraqi court so Saddam could answer for crimes allegedly committed against his own people.

Iraq’s insistence on the right to execute Saddam and his allies if they are convicted rules out holding the trial before an international court, such as the U.N. tribunals hearing cases from the Balkans and Rwanda.

Kubba suggested pro-Saddam insurgents were responsible for Tuesday’s killing. “We know that Saddam and his followers are ready to do anything when it serves their interest and to block the work of the court,” he said.

Saddam’s chief lawyer, Khalil al-Dulaimi, accused the Iraqi government, claiming the killing was carried out by “an armed group using government vehicles.” He repeated his previous demand that the trial be held in a neutral country.

Saddam and seven co-defendants went on trial Oct. 19 in a special court in the heavily guarded Green Zone. They are charged in the 1982 deaths of 148 Shiite Muslims in Dujail following an assassination attempt against Saddam in that town north of Baghdad.

Trial judge Rizgar Mohammed Amin postponed the proceedings until Nov. 28 to allow the defense time to prepare.

After the killing of the first lawyer, defense attorneys announced they would not cooperate with the court and would refuse to appear at the next session until they were satisfied with security. Kubba said the lawyers twice turned down invitations to move to the Green Zone, where they could be protected by U.S. and other international troops.

White House spokesman Scott McClellan acknowledged the necessity of ensuring “that you have the security environment in place for those trials to proceed and for witnesses to be able to participate in the trial as well in a secure way.”

In other developments Tuesday:

¢ The U.S. military said Marines and Iraqi troops had secured Husaybah after four days of fighting with al-Qaida-led insurgents in the town on the Syrian border. Commanders had described the town as a major entry point for foreign fighters sneaking into Iraq from Syria.

¢ Iraqi President Jalal Talabani, during a visit to Rome, repeated his prediction that his country’s security forces will be ready to begin taking over from coalition troops around the end of next year.

¢ One civilian was killed when gunmen opened fire in the Dora district in the capital.

¢ A car bomb exploded near Baghdad’s Mustansiriyah University, killing one person and injuring another.