Who are the five Iranian detainees?

Don't know yet, but apparently we should find out soon. The US military says they're from the Iranian Revolutionary Guard al-Quds Force, which it labels as "an organisation known for providing funds, weapons, IEDs, technology and training to extremist groups attempting to destabilise the government of Iraq and attack coalition forces." The US did manage to capture two top al-Quds officials in December last year, but let them go after a week following pressure from Iraq.

Even if the US is right about their affiliation, Borzou Daragahi at the L.A. Times complicates the picture by describing the Quds Force as "an elite intelligence and paramilitary organization," and the Revolutionary Guard as "a parallel army" that "controls Iran's borders as well as its foreign policy toward neighboring countries such as Iraq and Afghanistan." [My italics]

The biggest concern on the US side, among other things, seems to be that Quds is helping to supply advanced armor-piercing IEDs to Shiite militias, so the best question is not who the five Iranians were, but what they were doing: Directly helping militias attack US forces, providing consular services, or gathering intelligence? And if the latter, the next question is: what sort?


[Jan. 31st edit: added "providing consular services"]