The voice on the tape was identified by Al Jazeera as Abu Hamza al-Muhajer, also known as Abu Ayyub al-Masri, who took over from Abu Musab al-Zarqawi after the former leader was killed in a U.S. airstrike in June. However, CNN said it was unable to independently confirm the identity of the voice.
"I invite you not to drop your weapons and don't let your souls or your enemies rest until each one of you kills at least one American within a period that does not exceed 15 days with a sniper's gunshot or incendiary devices or Molotov cocktail or a suicide car bomb -- whatever the battle may require," Muhajer said on the tape.
In the 18-minute recording, the terrorist leader criticized Sunnis in Iraq for cooperating with the Shiite-led government but called for unity among Muslims "so the word of God can be the highest and the word of the infidels the lower."
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