A new scenario is suggested in order to explain the burst of particles observed by Giotto near the Halley ionopause. According to this scenario, an impact of a cometary dust particle against the Giotto spacecraft (Identified by Neubauer et al. (1990)) creates a gas/plasma cloud. Cold cometary ions with a velocity of 70 km/s that impinge on the cloud around the spacecraft are scattered by the secondary ions/neutral species in the cloud. This scattering is shown to allow the cometary ions to enter the angular detectors. This mechanism casts some doubt on alternative explanation of the observed phenomenon and thereby may call into question the very existence of suprathermal particles near the Halley ionopause. ¿ American Geophysical Union 1994