He is Muharib Abdul Latif al-Jubouri and was identified as the senior minister of information for al Qaeda in Iraq, said Maj. Gen. William Caldwell.
Caldwell said al-Jubouri was killed in a fight about four miles (six kilometers) west of the Taji air base north of Baghdad; the body initially was identified by photos, then confirmed by DNA testing on Wednesday.
Caldwell said al-Jubouri was believed connected with the 2006 kidnapping of American reporter Jill Carroll, who was released nearly three months later, and Tom Fox, one of four men from the Chicago, Illinois-based peace group Christian Peacemaker Teams, who was found fatally shot in Baghdad in March 2006.
Caldwell also tried to clarify reports of the deaths of two other key insurgents, Abu Ayyub al-Masri, the leader of al Qaeda in Iraq, and Abu Omar al-Baghdadi, the head of the Islamic State of Iraq.
The Islamic State of Iraq is an umbrella organization of Sunni militant groups that includes al Qaeda in Iraq.
Caldwell said the United States does not have the body of either man.
"We have nobody in our possession or know of anybody that does, alive or dead, that is going through any kind of testing or analysis at this point with respect to those two individuals," he said.
Caldwell said it is not known who al-Baghdadi is or whether he exists.
Iraq's Interior Ministry said al-Baghdadi has been killed and that it has his body. Iraqi state TV showed a body that it said was al-Baghdadi's.
Brig. Gen. Abdul Karim Khalaf, an Interior Ministry spokesman, claims al-Baghdadi was seriously wounded in a March 4 battle in the northern Iraqi province of Salaheddin, but he eluded capture. The battle was a result of a joint U.S.-Iraqi operation.
Khalaf said al-Baghdadi later died of his injuries, but it is not clear when.
Iraqi security forces, based on intelligence they have been tracking for some time, intercepted militants early Thursday carrying al-Baghdadi's body in the western Baghdad region of Ghazaliya.
In March, authorities arrested a man originally thought to be al-Baghdadi, but later learned he was a senior member of al Qaeda in Iraq.
On Tuesday, tribal leaders in Abu Ghraib and Falluja told the Iraqi government that al-Masri was killed in fighting.
Al-Masri is the "war minister" in the Cabinet of the Islamic State of Iraq -- which has claimed responsibility for a number of insurgent actions.
Iraqi authorities also said they can't confirm al-Masri's death, reports of which were dismissed by the Islamic State of Iraq.
A statement issued by the insurgent group said al-Masri is "safe" and "still battling the enemies of God."
Al-Masri is an Egyptian who replaced Abu Musab al-Zarqawi as head of al Qaeda in Iraq after al-Zarqawi's death in a U.S. airstrike last June.
By: A U.S. military commander said Thursday that an al Qaeda in Iraq militant believed to be involved in last year's kidnapping of journalist Jill Carroll has been killed.