Gunmen killed Iraq's most senior career diplomat as he was being driven to work Saturday morning. It was the first assassination of a top Iraqi official since the new interim government took office 12 days ago.

Bassam Salih Kubba had just left his home in the Adhamiya suburb north of Baghdad when gunmen in a black sedan fired at his car, striking Kubba fatally and injuring his driver, relatives said. Kubba died as his driver sped to the hospital in the unarmored white Mercedes, its back windows shattered by bullets.

Kubba, 60, was appointed as a deputy foreign minister two months ago but had worked at the ministry since 1968. He served as former president Saddam Hussein's ambassador to China and was chief of Iraq's mission to the United Nations. He was on the committee that ran the Foreign Ministry after Hussein's overthrow last year.

High-profile Iraqi officials associated with the U.S.-led occupation authority and the transitional government have been targeted repeatedly by insurgents in the weeks leading up to the June 30 transfer of power.

The head of the now-disbanded Iraqi Governing Council, Izzedin Salim, was killed in a suicide car bombing May 17 at an entrance to the heavily guarded headquarters of the occupation. Two days later, a car bomb exploded outside the home of Abdul-Jabbar Youssef Sheikhli, a deputy minister in Iraq's Interior Ministry, wounding him and his wife and killing five civilians.

On Wednesday, Deputy Health Ammar Safar escaped an assassination attempt in the same Sunni Muslim area of Baghdad where Kubba was gunned down. Safar was also on his way to work when he was attacked. His guards exchanged fire with the attackers, who then fled.

A statement from Iraq's Foreign Ministry blamed the assassination of Kubba, a Shiite Muslim, on "leftover supporters of Saddam Hussein."

"We are saddened to lose such a close friend and a highly capable diplomat who has been helping our efforts to rebuild the Foreign Ministry," said Foreign Minister Hoshyar Zubari. "We will not be scared or intimidated by Saddamists to continue our work to consolidate the reintegration of Iraq as a peaceful and responsible member of the international community."

Another Iraqi career diplomat, Akila Hashimi, was killed in September in an ambush near her Baghdad home. Hashimi was also a Shiite.

Meanwhile, in Najaf, Adnan Zurufi, the governor of the southern city, told a reporter on Saturday that U.S.-supported Iraqi security forces would continue to deal on their own with the militia of defiant Shiite cleric Moqtada Sadr, which has been battling U.S. troops on and off for weeks.

Zurufi said he sent a letter to Sadr asking him to withdraw his Mahdi Army militia as soon as possible from the holy city. He said he has supplied the local Iraqi police with weaponry, including sniper rifles and rocket launchers, to use against the militia, which violated a five-day old truce on Thursday. "Any side that does not abide by the maintenance of security, we shall deal with severely," Zurufi said at a press conference.

During prayer services on Friday, an aide to Sadr told worshipers that the cleric would support the new interim government in Iraq, but only if U.S. and other occupation forces set a timetable for leaving the country. The conciliatory gesture was part of a continuing trading of statements between Sadr, the Shiite caucus in the interim government and Grand Ayatollah Ali Sistani, Iraq's most respected and influential Shiite cleric.

In Baghdad on Saturday, relatives and neighbors mourned Kubba, a well-traveled man with a degree in international relations from St. John's University in New York.

The neighbors and relatives said Kubba shunned the bodyguards and extra security that many officials use, preferring to live as normal a life as he could. They said he walked to local shops many afternoons with his wife to buy groceries. She had been on a trip to London to visit their son and learned the news from television in Jordan, where she was on her way back to Baghdad on Saturday.

Mohammad Ibraheem, who sells satellite dishes and electronic goods at shop near where Kubba lived, expressed shock when told of the assassination. "Bassam? Don't tell me that," he said, shaking his head in disbelief. "He was a very nice guy, very simple. All the people liked him. I hope he did not die. I hope it's a lie."

Ibraheem said that after Kubba became deputy minister, his friends tried to persuade him to hire bodyguards. "We told him many times that he should have guards when he walks around," said Ibraheem. "We told him that he was an ambassador and a deputy minister. He refused. He asked why he should get guards and bring attention to his house."

Dan Senor, the top spokesman for the Coalition Provisional Authority in Iraq, said occupation authorities provide security for Iraqi officials who request it or funding and training for their own personal security forces. He said the officials make their own decisions concerning the level of security to apply.

"Security for the Iraqi governing officials is a very high priority for the coalition," he said. "While there have been some tragedies . . . that have been horrible, I think it's significant to note that a large number of tragedies have been averted."

In other attacks in Iraq on Saturday, a bomb wounded two soldiers outside the city of Baquba, 30 miles northeast of Baghdad, the U.S. military said.

Army Brig. Gen. Mark Kimmitt, the chief military spokesman, also said that the U.S. military would release 650 more prisoners from the Abu Ghraib prison on Monday. The military plans to reduce the number of detainees at Abu Ghraib to about 1,500, down from more than 3,000 a month ago.

[Elsewhere, a Lebanese Foreign Ministry official said a Lebanese construction worker had been shot dead by kidnappers and his body found near Fallujah on Saturday, according to the Associated Press. The official, Mohammed Issa, said the worker was among three Lebanese who had been abducted in Iraq, but he did not say when. One was freed and the other is missing, AP reported. Meanwhile, seven Turkish contractors who had been abducted while working for a construction company were freed in Fallujah by their captors, according to AP.]

Special correspondents Naseer Nouri in Baghdad and Saad Sarhan in Najaf contributed to this report.

Bassam Salih Kubba was a deputy minister and career diplomat.