Iraqi authorities have exhumed the remains of 15 people from a mass grave believed to hold dozens more likely killed under dictator Saddam Hussein, an official said Saturday. The mass grave was first discovered in April near the southern city of Najaf, during work to build a residential compound. It is believed to date back to the 1990s, when Saddam unleashed a deadly campaign against members of the majority Shiite Muslim community in southern Iraq that left nearly 100,000 dead.