The main purpose of topic detection and tracking (TDT) is to detect, group, and organize newspaper articles reporting on the same event. Since an event is a reported occurrence at a specific time and place, and the unavoidable consequences, it is conceivable that place information in a news article plays an important role in TDT. We analyzed news articles for their characteristics of place information and devised a new topic tracking method incorporating the analysis results. Experiments show that appropriate use of place information indeed helps identifying news articles reporting on the same events.