As CBS News National Security Correspondent David Martin first reported Monday, Abdullah Abu Azzam was a top aide to the organization's leader, Abu Musab al-Zarqawi, controlling finances for the group's foreign and Iraqi fighters and running its operations in the capital.
He was on a U.S. military list of the 29 most wanted insurgents in Iraq, issued in February. The military had put a $50,000 reward on his head.
Al Qaeda in Iraq has been one of the most prominent guerrilla groups in Iraq, carrying out devastating suicide attacks that have killed hundreds.
It was not immediately clear what effect Abu Azzam's death would have on the group. The U.S. military has claimed to have killed or captured leading al-Zarqawi aides in the past and attacks have continued unabated — though Abu Azzam appeared to be a more significant figure.
Meanwhile, a suicide bomber with explosives hidden under his clothing, slipped into a police building in Baqouba, 30 miles north of Baghdad, where the Iraqis were submitting applications to join Iraq's Quick Reaction Police Force, said a police commander, who spoke on condition of anonymity because of concerns about his security.
Nine Iraqis were killed and 21 wounded in the blast, said Adhid Mita'ab, an official in Baqouba General Hospital.
In other developments: