Co-aligned images of the active region taken before (top panels) and after (bottom panels) the M6.0 flare that occurred on 2011 August 3 at 13:17 UT. Left panels: Hα images acquired by the Big Bear Solar Observatory. Middle panels: SDO/AIA images acquired at 193 Å. Right panels: SDO/HMI magnetograms. The white arrows in the top images indicate the location of two filaments. The red contours on the HMI magnetograms outline the shape of the analyzed filaments derived from the AIA 193 Å images. The x and y scales are arcseconds. North is at the top of the images and west to the right.