BAGHDAD, Iraq (CNN) -- The U.S. military on Wednesday announced the arrest of a senior leader of al Qaeda in Iraq, an insurgent who, the military said, is casting himself as a "conduit" between the top leaders of al Qaeda and al Qaeda in Iraq.
Khalid al-Mashadani was seized in Mosul, the U.S. military says.
Khalid al-Mashadani, an Iraqi also known as Abu Shahed, was seized on July 4 in the northern Iraqi city of Mosul and is in coalition custody, the military said.
"He served as the al Qaeda media emir for Baghdad and then was appointed the media emir for all of Iraq," said Brig. Gen. Kevin J. Bergner, Multi-National Force-Iraq spokesman, who briefed reporters.
He is believed to be the most senior Iraqi in al Qaeda in Iraq.
During interrogations, al-Mashadani shed light on the workings of al Qaeda in Iraq and its connection with al Qaeda outside of Iraq, Bergner said.
He said al-Mashadani is a close associate of al Qaeda in Iraq leader Abu Ayyub al-Masri and served as an "intermediary" between al-Masri, al Qaeda leader Osama bin Laden and Ayman al-Zawahiri, the second-in-command of al Qaeda.
"In fact, communication between senior al Qaeda leadership and al-Masri frequently went through al-Mashadani," Bergner said.
Bergner said al-Mashadani co-founded an organization "in cyberspace" called the Islamic State of Iraq, which he referred to as a "marketing" effort to create a Taliban-like state in Iraq. Watch Bergner's briefing to reporters »
U.S. counterterrorism officials also told CNN that al-Mashadani was a top lieutenant to al-Masri and regarded as a "jack of all trades," involved in recruitment and in organizing and planning attacks, with particular interest in propaganda activities.
One of those officials said the announcement of his arrest was delayed because officials wanted to "maximize their ability to get information" from him before others he was associated with knew about his detention.
Al-Mashadani also shed light on the Islamic State of Iraq, the so-called umbrella group of Iraqi insurgents that includes al Qaeda in Iraq.
That group has claimed responsibility for many terrorist attacks.
But Bergner said that al-Mashadani passed on the information that the creation of the group was a ruse to cast itself as home-grown, when in fact it is led by foreigners.
It went so far as to create a fictional political head of Islamic State of Iraq, Omar al-Baghdadi and an actor was used to portray him.
Bergner said Islamic State of Iraq is "a front organization" for al Qaeda in Iraq and a "pseudonym" for it as well.
"It is really being controlled, directed and guided by al Qaeda in Iraq leadership."
Bergner also said al-Mashadani was a leader in the Ansar al Sunna terrorist group before joining al Qaeda in Iraq two-and-a-half-years ago.
What the U.S. military has learned from al-Mashadani and other operatives they've seized is that "there is a flow of strategic direction, of prioritization of messaging and other guidance that comes from al Qaeda senior leadership to the al Qaeda in Iraq leadership," Bergner said.
Bergner emphasizes that that there is a "clear connection between al Qaeda in Iraq and al Qaeda senior leadership outside Iraq."
The arrest of al-Mashadani was announced amid controversy over President Bush's contention that al Qaeda and al Qaeda in Iraq are one and the same. The evidence has been not been significant about the extent of the relationship.
But a new U.S. government intelligence analysis released Tuesday said al Qaeda's terrorist activities in Iraq not only serve to bolster the group and recruit more members, but may also be the nexus for another planned attack on U.S. soil.
The declassified portion of the National Intelligence Estimate (NIE) warns of "a persistent and evolving terrorist threat over the next three years" from Islamic terrorist groups, namely al Qaeda.
Al Qaeda is increasing its efforts to get operatives into the United States for an attack and has nearly all the capabilities it needs to carry out such a mission, according to the report, which represents the combined analyses of all 16 U.S. intelligence agencies. E-mail to a friend
CNN's Pam Benson contributed to this report.