"Mosul is the strategic center of gravity for al-Qaida," Air Force Col. Donald Bacon said. "Our assessment is that (al-Qaida) can't survive without the networks in Mosul."
Bacon, the chief of special operations for U.S.-led forces in Iraq, categorized Mosul as the financial hub of al-Qaida and other foreign militant groups operating in the area.
He said that Ninawa province, of which Mosul is the capital, is the only province in Iraq not experiencing a lull in violence following the troop surge. Bacon said more than half of all daily violent attacks in Iraq lately occur in and around Mosul, the American Forces Press Service said.
U.S.-led forces captured or killed hundreds of militants in Mosul since January. One of those captured was a reported al-Qaida military leader, Bacon said, and another was the leader of the al-Qaida network operating in southeastern Mosul.
The grassroots security force known as Sons of Iraq was responsible for discovering several weapons caches and other reconnaissance efforts in the area, but Bacon noted the fight would continue against remaining al-Qaida operatives throughout Iraq.
"It's going to be a continuous fight, where we just keep chipping away at them," he said.
Notable deaths of 2014 [PHOTOS]