A method for the detection of explosives using a single sample. The explosives include nitro aliphatic and nitro aromatic-based explosives. The method includes steps which require different pHs to discriminate between these types of explosives and at least in the detection step of the nitro aliphatic explosive requires the presence of a nitro aromatic compound. A kit for detecting explosives which includes a medium for collecting a sample, a base optionally impregnated on the medium and a nitro aromatic solution for detecting a nitro aliphatic explosive by contacting the solution with the sample on the medium. A reagent including a nitro aromatic compound, having one or more additional electron withdrawing groups, in the presence of a basic compound usable for detecting nitro aliphatic explosives.