The mutagenic compounds 2-amino-6-methyldipyrido[1,2-alpha:3',2'-d]imidazole (Glu-P-1) and 2- aminodipyrido [1,2-alpha: 3',2'-d]imidazole (Glu-P-2), which were isolated from a glutamic acid pyrolysate and are potent carcinogens in the liver and brown adipose tissue of mice, were found to be multipotent carcinogens in rats. These compounds were each given to F344 rats of both sexes at a concentration of 500 ppm in pellet diet for up to 24 months. Glu-P-1 induced tumors in the colon, small intestine, liver, Zymbal gland, clitoral gland and brain. Glu-P-2 produced tumors in the same sites at slightly lower incidence. The multipotent carcinogenicities of Glu-P-1 and Glu-P-2 in rats and mice suggest that heterocyclic amines present in cooked food may be important in the development of human cancer.