This paper describes two techniques for detecting dynamic events using the motion vectors obtained from the MPEG video encoding. In the first technique, feature vectors from motion information form a high dimensional curve for a video clip, and curve simplification allows us to browse the clip along portions where interesting events are likely to happen. In the second technique, the camera motion, pan, tilt, and zoom are computed from the motion vectors, and the residual vectors which are not explained by the camera motion are regarded as generated by moving blobs. Events are detected from these moving blobs.