The invention relates to a method for detecting an explosive substance which contains chlorate, bromate and/or organic peroxide, wherein a suspect substance is contacted with a first reagent, which is a strongly acid solution of at least one primary or secondary aromatic amine, whereby chlorate or bromate type explosive affords a distinct coloration; and in the absence of such coloration, contacting the same sample (in contact with the first reagent) with a second reagent, which is a solution comprising cations of at least one transition metal, whereby the presence of organic peroxides in the sample, which has been hydrolyzed at least partly to hydrogen peroxide by the strong acid of the first reagent, affords a distinct coloration. The invention further relates to a kit containing separate first and second reagents; a container of mixed reagents for detecting peroxide; and a kit including such container.