XMM-Newton images of the DS Tuc system. Top panel: MOS 2 image of DS Tuc with the regions used for accumulating source and background events. The scale is logarithmic to enhance the background level otherwise not visible on a linear scale. The background region was offset to one of the corner of the chip to avoid the diffraction spikes from the central source. Bottom left: image of MOS 1 during the first 6 ks of observation and corresponding to interval 1 in Fig. 2. We marked the SIMBAD positions (J2000) of DS Tuc A and B and the vectors of proper motions. Bottom right: image during interval 3 corresponding to the peak of the first flare. In both images, the scale limits and color maps are identical, the binning is 8 pixels corresponding to ∼0.4″ and a smoothing with a Gaussian with σ = 1.5 pixels has been applied to images. We added contour levels with the same ranges for marking the source centroid.