Baghdad ? Iraqi police commandos captured the leader of al-Qaida in Iraq in a raid in the northern city of Mosul, Iraqi officials said Thursday, in what could mark a significant blow to the Sunni insurgency in its last urban stronghold.

Iraqi Defense Ministry Spokesman Mohammed al-Askari said the arrest of Abu Ayyub al-Masri – also known as Abu Hamza al-Muhajir – was reported by the Iraqi commander in Mosul, where insurgents have sought to establish a foothold after being widely uprooted from Baghdad and surrounding areas last year.

The U.S. military in Baghdad said it was “checking with Iraqi authorities to confirm the accuracy of this information.”

Interior Ministry spokesman Maj. Gen. Abdul-Karim Khalaf said the arrest occurred “at midnight and during the primary investigations he admitted that he is Abu Hamza Al-Muhajir.”

Khalaf told the Iraqi state television that al-Masri was arrested during a police raid, but gave no other details.

“Now a broader investigation of him is being conducted,” he said.

His apprehension would carry major symbolic value for Iraqi commanders, who have led operations in the Mosul area and have sought to counter worries that Iraqi forces lack the training and discipline to wage a head-on fight against insurgents.

But it’s unclear how much the reported loss of al-Masri would disrupt al-Qaida in Iraq or its long-term ability to wage suicide attacks and other strikes. Al-Masri took over al-Qaida in Iraq after its leader, Abu Musab al-Zarqawi, was killed June 7, 2006, in a U.S. airstrike northeast of Baghdad.

But the pace of insurgent attacks remained strong as al-Masri took charge.

“The commander of Ninevah military operations informed me that Iraqi troops captured Abu Hamza al-Muhajir the leader of al-Qaida in Iraq,” al-Askari told The Associated Press by telephone.

There have, however, been false alarms in the past about al-Masri. At least twice – in 2006 and May 2007 – reports circulated that al-Masri was dead, but they were later proved wrong.

Any direct links are murky between al-Masri’s insurgents and the terror network of Osama bin Laden. But al-Masri has followed a path that brought him in contact with some of bin Laden’s top lieutenants.

U.S. officials said al-Masri – whose name means “The Egyptian” in Arabic – joined al-Qaida camps in Afghanistan in the late 1990s and trained as a car bombing expert before traveling to Iraq after the U.S.-led invasion in 2003.

The U.S. military also described al-Masri as a previous member of the extremist Islamic Jihad in Egypt and a protege of Ayman al-Zawahiri, who became bin Laden’s No. 2 after the group joined with al-Qaida in 1998.

The Islamic State of Iraq, an umbrella organization that includes al-Qaida in Iraq, last year announced an “Islamic Cabinet” for Iraq and named al-Masri as “minister of war.” The U.S. military had put a $5 million bounty for al-Masri.

The arrest was also significant for its location.

Mosul was considered the last important urban staging ground for al-Qaida in Iraqi and allied groups after losing strongholds in Baghdad and other areas during the U.S. troop “surge” last year.