A judge on the special tribunal that will put Saddam Hussein and members of his former regime on trial was assassinated in the Iraqi capital, officials said Wednesday. Judge Barwez Mohammed Mahmoud and his brother were killed Tuesday in northern Baghdad's Azamyiah district, police 1st Lt. Oday Kayoun told The Associated Press. On Wednesday, a car bomb exploded outside an Iraqi army base in central Baghdad, killing six soldiers and wounding 25, police said. The blast occurred at a base located at the former Muthanna airport, police officer Salam Hashim Mahmoud said. The violence came as thousands of mostly black-clad Iraqis protested outside a medical clinic in Hillah, a city 100 kilometers (60 miles) south of the capital where a suicide car bomber killed 125 people a day earlier. The protesters, braving the threat of another attack as they waved clenched fists, condemned foreign fighters and chanted "No to terrorism!"