Maps of the integrated intensity of the ¹²CO(3–2), (6–5) and (7–6) lines in the velocity range v_LSR = [−54, −40] km s^-1 (color scale). Solid contours are the integrated intensity of the ¹²CO(6–5) line from 20% of the peak emission in steps of 10%. In each panel, the positions analysed in Sect. 4.2 (the hot core, the IRDC position, and the centre of the Hii region) are marked with black triangles. The red star labels the position of the EGO. SMM6 (left panel) is one of the submillimetre sources detected by Minier et al. (2009).