Results of the double component fit to the [O III] (top) and Hα (bottom) lines. Left and middle panels: Velocity fields of the high-velocity and low-velocity narrow components, following the colour bar to the right, are shown. White denotes regions where a single Gaussian fit is preferred (see Sect. 3.5). Rightmost panels: PV diagrams as in Fig. 10, but this time we use blue and red points to denote the velocities of the low- and high-velocity components, respectively, and green points to denote the velocities obtained from the single Gaussian fitting. For comparison, we overplot the [N II] (filled brown squares) and stellar (open black stars) velocity curves along the same PA.