Mexico''s government promised to investigate photographs showing a drug kingpin''s bullet-ridden body covered in bloodstained money after he was killed in a gunbattle with troops.

Interior Secretary Fernando Gomez-Mont said Friday the photographs of Arturo Beltran Leyva are humiliating and contract the government''s public relations policy.

"It''s unnecessarily offensive to the family of these people", Gomez-Mont told Televisa network.

Mexican media published photos of Beltran Leyva''s half-naked body covered in bloody bills in the apartment where he died Wednesday in a gunbattle with marines.

Navy spokesman Rear Adm. Jose Luis Vergara told The Associated Press that no marine took that picture or put the bills on the body. He did not say who might have done it, saying the matter was under investigation.

Beltran Leyva, nicknamed the "boss of bosses", is the highest-ranking figure taken down in President Felipe Calderon''s three-year-old drug war.

U.S. and Mexican officials say Beltran Leyva carried out heinous killings, including numerous beheadings, and had great success in buying off public officials and police to protect his cartel.

Mexican marines acting on information from U.S. officials stormed the upscale apartment building in the central city of Cuernavaca and demanded the surrender of Beltran Leyva. Authorities say gunmen fired on the marines who then launched an attack that lasted nearly two hours.

Six gunmen and one marine died.

Vergara said marines found Beltran Leyva lying dead in the entrance of the apartment with his pants down to his knees and his T-shirt pulled up to his shoulders. He suggested that perhaps the druglord''s own bodyguards loosened his clothing while attempting to him.

Beltran Leyva was the most powerful of several brothers in charge of the crime syndicate named after them. Mexican authorities arrested one of the brothers, Alfredo Beltran Leyva, in January 2008.