He said there was "no question" but that Iran had supplied arms, training, funding and in some cases the direction for operations to Iraqi militants. Iran denies involvement.
Petraeus told reporters also that Iran's ambassador to Baghdad, Hasan Kazemi-Qomi, was a member of the Quds Force of Iran's elite Revolutionary Guards.
The Iranian Embassy in Baghdad had no immediate comment.
RFE/RL Iraq Report
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