K_s-band difference images showing the temporal evolution of the burst and the associated LEs, displayed using a log scale. The prompt echo, which originates from the cloud core, is monopolar and spreads to the southeast at an PA of ∼135°. A remote LE that appeared later traces denser structures of the ISM. The red polygon encloses the area from which its light curves were established. The FoV is 135″ × 80″.