From this:

(Rep. Peter King) and several members of the House Republican leadership filed a resolution of inquiry on Wednesday that would give (Janet Napolitano) 14 days to provide Congress with materials detailing how the Department of Homeland Security arrived at the conclusions contained in the [rightwing extremist report].

Whether the resolution will do anything and will produce, for instance, details on the extent to which materials from far-left groups like the Southern Poverty Law Center or the Anti Defamation League were used as sources isn't clear.

The resolution follows a letter:

In the April 25 letter to (Bennie Thompson), Napolitano explained that the message in the report - "Right-wing Extremism: Current Economic and Political Climate Fueling Resurgence in Radicalization and Recruitment" - could have "been made more directly and succinctly" and admitted that "there was a breakdown in the clearance process before its distribution."