For the first time since the flare up of sectarian violence, a top Pentagon general is directly blaming the Iranian government for supporting and even training Shiite terror groups in Iraq.

"I think it is a policy of the central government of Iran to support the Shiia extremist groups in Iraq," Brig. Gen. Michael Barbero of the Pentagon's Joint Chiefs of Staff told reporters on Wednesday. "I have seen reports of their involvement and presence there as trainers to train these terrorist and Shiite extremists groups."

Sunni and Shiite extremists in Iraq have been attacking each other with regularity since February, making 2006 a much more deadly year for Iraqis than any other time since the U.S.-led invasion in March 2003. Last month, 3,500 Iraqis were killed in the sectarian violence sweeping Iraq, the deadliest month on record.

In March, Defense Secretary Donald Rumsfeld said Iranian Revolutionary Guards were in Iraq. The Pentagon has consistently called the Iranian as well as Syrian governments' stand on Iraq "unhelpful."

Barbero would not say how many Iranian trainers he believes have been in Iraq or when they were there.

"I don't have exact timelines or examples but the evidence I've seen is clear they have been involved in direct support to these Shiite extremists groups. They have been involved in inciting the sectarian violence," he said.

FOX News' Mike Emanuel and Nick Simeone contributed to this report.