Related Event: Iraq in Transition

U.S. forces said on Thursday they had detained a senior associate of Jordanian militant Abu Musab al-Zarqawi, al Qaeda's leader in Iraq, while Spain announced on Wednesday the arrest of 11 suspected Zarqawi followers.

"We've become used to the lies of the crusaders and their followers. Every now and then they hold a Muslim and say they have captured an aide to Sheikh Zarqawi," the statement said.

"Spain claimed it has arrested a group of Zarqawi aides. Each Muslim, now is suspected of belonging to al Qaeda," said the statement signed by the group's spokesman Abu Maysarah al-Iraqi.

"In Mosul, the enemies of God claimed to have arrested a senior official and aide to Zarqawi...We tell you that your brothers are well...and continuing their jihad," it added.

The statement could not be immediately authenticated.

U.S. forces said they had captured Mohammed Khalif Shaiker, also known as Abu Talha or the emir of Mosul, on Tuesday in Iraq's third largest city.

Zarqawi's group has claimed responsibility for some of the deadliest bombings in Iraq.

In December last year, U.S. forces in Mosul announced the capture of one of Shaiker's deputies, Abdul Aziz Sa'dun Ahmed Hamduni, also known as Abu Ahmed, and the next day seized another deputy.