A significant amount of background data was collected as part of May 2005 tests at an arid site for airborne minefield detection. An extensive library of the target chips for MSI (four bands) and MWIR sensors for false alarms and mines was created from this data collection, as discussed in another paper in the same proceeding. In this paper we present some results from the analysis of this background data to determine spectral and shape characteristics of different types of false alarms. Particularly, a set of spectral features is identified that can be used for effective false alarm rejection for the benefit of airborne minefield detection programs. A reasonable separation between vegetation and non-vegetation (like rocks) is shown for Normalized Difference Vegetation Index (NDVI) type metrics. Also, a reasonable separation is shown between different types of false alarms at a given time using Color Contrast feature. The spatial distribution of different types of false alarms, as seen in available airborne background data, is also evaluated and discussed. Such spatial analysis is of interest from the perspective of minefield level detection and analysis. The paper is concluded with a discussion on future directions for this effort.