U.S. military officials say a convoy of private contractors has been ambushed in southern Iraq and up to 14 people have been kidnapped.
The officials say four Americans are believed to be among those who were kidnapped at a checkpoint near Nassiriyah. Coalition forces are searching for the victims.
Media reports say the convoy of 19 vehicles was run by a Kuwait-based company called the Crescent Security Group and that it was driving from the Kuwait border to a base near Nassiriyah.
The reports say the convoy stopped at what looked like an Iraqi police checkpoint. It is not clear whether the checkpoint was operated by Iraqi police or Shi'ite militiamen.
A U.S. official told the Associated Press some of the convoy drivers have been released and are being interviewed by the U.S. military.
The Crescent Security Group says on its website that it escorts convoys and assists with security missions. It says it is hired by coalition militaries, embassies, and private companies.