BAGHDAD — Gunmen assassinated a high-ranking Sunni judge as he headed to work in Baghdad yesterday, the latest of thousands of professionals killed in unsolved cases since the ouster of Saddam Hussein’s regime in 2003.

Appeals Court Judge Amir Jawdat al-Naeib was slain a week after police arrested a group of militants who specialized in intimidating or killing doctors, academics, and judges, according to an Interior Ministry official.

The aim of such attacks is to empty the country of professionals and scientists, the official said, speaking on condition of anonymity because he was not authorized to talk to the press.

Under Saddam’s Sunni-led regime, members of the now-dissolved Baath Party made up much of Iraq’s professional class, including senior bureaucrats who knew how to run ministries, university departments, and state companies. After his overthrow, senior Baathists were purged from their jobs, some were assassinated and many fled the country.

A key piece of legislation adopted Sunday by Iraq’s Parliament would allow thousands of low-ranking former Baathists to return to government jobs. But many former Baathists say they would not take such positions back, fearing Shiite death squads would hunt them down.

Some Iraqis blame Iranian-backed militias and hit squads for many of the killings — particularly of former army officers who took part in Iraq’s ruinous 1980–88 war with Iran. Criminal gangs are also believed to be involved in some cases. Naeib, who was also a member of the Supreme Judicial Council, was ambushed by gunmen in two cars in the Mansour district of western Baghdad as he was being driven from his home.