RIO DE JANEIRO (AP) — U.S. Defense Secretary Jim Mattis says he heard gunfire early Tuesday during his stay in Rio de Janeiro.

There was no indication that the gunshots, which Mattis said he could hear from his hotel room near the city's Copacabana beach, were linked to his visit or that he was in any danger.

Asked about reports that a pre-dawn gunfight among drug groups had erupted in the vicinity of his hotel, Mattis says it saddened him but he knew no details.

Local media reported shootouts early Tuesday between drug trafficking gangs in nearby slums. Greater metropolitan Rio has more than 1,000 slums. Many are controlled by drug traffickers or militias, comprised of former police and military, and shootouts are common.