JAKARTA (Reuters) - Indonesia's president has ordered security authorities to investigate allegations of police involvement in the illegal distribution of drugs in the world's most populous Muslim-majority nation.

Haris Azhar, a prominent activist with the Commission for Missing Persons, said this month that drug trafficker Freddy Budiman confessed to him in 2014 that he had given police, military and customs officials millions of dollars in bribes to protect his drug smuggling business.

Budiman and three other drug traffickers were executed by firing squad on July 29.

"Trace, investigate and process the allegations if it is indeed true," President Joko Widodo said in a statement issued late on Thursday, ordering the police chief to create a team to investigate the claims.

Widodo, who has made fighting drug crimes in one of Southeast Asia's biggest markets a top priority, questioned why the allegations were not brought to light earlier.

(Reporting by the Jakarta bureau; Writing by Randy Fabi; Editing by Paul Tait)