A suicide car bomber in the Iraqi capital struck a convoy carrying Iraqi police Thursday, killing at least six officers and wounding more than 20 others.

Authorities say the bombing occurred on Baghdad's notorious airport road, the scene of numerous car bombings and deadly ambushes over the past two years.

Earlier Thursday, an Iraqi judge and his driver were gunned down in the northern city of Mosul.  In Kirkuk, at least six Iraqis were wounded when a suicide car bomber blew himself up near an Iraqi army convoy.

Meanwhile, the U.S. military says it has captured the regional al-Qaida militant leader for Mosul.

A statement identified the insurgent as Muhammad Khalaf Shakar, also known as Abu Talha.  It said multiple sources led U.S. troops to the suspect's hideout, where he surrendered without incident. 

The U.S. military also said five Marines were killed Wednesday in a roadside bomb blast near Ramadi.  A U.S. sailor also died during combat operations the same city.

Some information for this report provided by Reuters and AFP.