http://www.iht.com/articles/2007/01/11/news/iran.php
The American officials say that the Iranian Revolutionary Guard's Quds force trains inside Iran and then dispatches operatives into Iraq, using contacts with Iraqi Shiite militias to attack American troops. "They're training to kill coalition forces," said one senior American counterterrorism official, requesting anonymity. "Their comments about wanting to see a stable Iraq are belied by this type of activity."