This study focuses on investigating the ability of selected satellite-derived indices, the normalized multi-band drought index (NMDI), normalized difference water index (NDWI), and the normalized burn ratio (NBR), for detecting forest fires burning in southern Georgia, USA and southern Greece in 2007. Index performance is evaluated using MODIS fire products. Satellite images generated from each index are compared with the active fire map provided by the MODIS rapid response team. Performance measures extracted from the statistical analyses using the confusion matrices are used to verify the capacity of the indices for active fire detection. For each test case, NMDI has strong signals corresponding to active fires and pinpoints the active fire spots accurately. Both, performance evaluations by image comparison and statistical analyses, indicate that active fire detection using NMDI is quite accurate. NMDI reveals the highest overall performance and discrimination power compared to NDWI and NBR. The successful application of NMDI for detecting fires in different areas proves that NMDI is not site-specific and is expected to be applicable to different areas for active fire detection. Such a capacity can help monitor large-scale fire hazards and is therefore useful to carry out regional and global studies.