In this article we report interplanetary scintillation observations at 103 and 327 MHz of an Earth-directed coronal mass ejection (CME) which occurred near the center of the solar disk at 0435 UT on May 12, 1997. The disturbance was found to have plasma density ~4 times more than that of the ambient plasma at a distance of ~0.5 AU from the Sun. The most peculiar aspect of this CME is that it appears that the disturbance moved slightly slower than the ambient medium. Solar and Heliospheric Observatory (SOHO) and interplanetary scintillation (IPS) estimates of solar wind are quite different; it appears that the difference could be due to the projection effect of the SOHO image. Though the disturbance was not very severe, its impact on Earth's environment produced a geomagnetic storm. This event was associated with a two-ribbon flare. The ionospheric effects of soft X rays from this solar flare were observed by a digital ionosonde at Ahmedabad in the form of excess ionization (~1200 el cm-3) in the D region of the ionosphere. ¿ 2001 American Geophysical Union