摘要: This paper addresses the problem of automatic detection and prediction abnormal human behaviours in public spaces. For this propose a novel classifier, called N-ary trees, is presented. The classifier processes time series attributes like object position, velocity, perimeter area, to infer type action performed. innovative can detect three types events: normal; unusual; or events. In order evaluate performance trees we carry out preliminary study with 180 synthetic tracks one restricted area. results revealed great level accuracy that proposed method be used surveillance systems.