BAGHDAD, Iraq — A judge on the special tribunal that will put Saddam Hussein and members of his former regime on trial was assassinated Tuesday in the Iraqi capital, according to an Iraqi police official and a media report.

Judge Barwez Mohammed Mahmoud and a relative were killed Tuesday in northern Baghdad's Azamyiah district, the official told The Associated Press early today on condition of anonymity.

Al-Arabiya, the Dubai-based satellite TV news network, also reported that the judge and a relative died in an attack. The judge's exact relationship to the other victim wasn't immediately known. The network said they lived in the same house in northern Baghdad, near the attack site.

Officials with the Iraqi government and the Iraqi Special Tribunal couldn't be reached before dawn today for comment.

Mahmoud's role on the tribunal was unclear, but the law establishing it called for up to 20 investigative judges and up to 20 prosecutors. It also said the tribunal would have one or more trial chambers, each with five judges. The judges have not even been identified in public because of concerns for safety.

The killing came just one day after five former members of Saddam Hussein's regime — including one of his half brothers — were referred to trial for crimes against humanity.

The announcement Monday by the tribunal marked the first time that the special court issued referrals, similar to indictments, which are the final step before trials can start.

No date was given for that trial.

The five referred to trial Monday included Barzan Ibrahim al-Hassan al-Tikriti, one of Saddam's half brothers, and former vice president Taha Yassin Ramadan. The three others were senior Baath Party members.

Saddam was captured in December 2003, and others have been in custody for nearly two years.

U.S. military officials transferred 12 of the top defendants to Iraqi custody in June with the handover of sovereignty. They're being held at an undisclosed location near Baghdad International Airport, west of the capital.