Mosul is a city in northern Iraq and the capital of the Nineveh Province, some 400 km (250 mi) northwest of Baghdad.
The Army of the Nineveh Province confirmed the report in a Saturday statement, adding that16 arrest warrants were issued to capture the al-Qaeda ringleader in the north of the country.
The detained al-Qaeda terrorist was transported to a security center for further investigations.
Nineveh security forces also killed two members of the al-Qaeda-linked Islamic State of Iraq and Levant (ISIL) and arrested six others on Saturday.
Al-Qaeda militants, emboldened by the conflict in neighboring Syria, have sought to position themselves as the champions of Sunnis against the Iraqi government, though major Sunni tribes in Anbar and elsewhere oppose the group's extremist ideology and are fighting against it.
Iraqi Prime Minister Nouri al-Maliki has previously called for national unity among Iraqis in the war against al-Qaeda.
RA/MB