The U.S. government charges that Iran has been involved in the deaths of American soldiers. The U.S. recently arrested men it describes as Iranian agents inside Iraq. In an interview with NPR, Undersecretary of State Nicholas Burns offered few details, but said the Iranians played an active role.
"We have picked up individuals who we believe are giving very sophisticated explosive technology to insurgent groups, who then use that technology to target and kill American soldiers," Burns said. "It's a very serious situation."