The speaker was identified as Abu Hamza al-Muhajir, also known as Abu Ayyub al-Masri, on several Islamist Web sites that posted the recording.

By April 19, 4,036 U.S troops had died in the Iraq war.

The speaker also called for attacks on members of Iraqi awakening councils, a movement of predominantly Sunnis who have joined forces with the U.S and Iraqi governments in battling Islamic Jihadists loyal to Al Qaeda in Iraq.

Also on April 19, radical Shiite cleric Muqtada al-Sadr threatened to “declare a war” unless U.S and Iraqi forces stop their assaults on his followers.