Former senior police officer Eduardo Acierto, who has been the target of death threats, has submitted a report and believes Chinese drug smuggling syndicates may have access to the top levels of the Philippines government.
Acierto has pointed to a Chinese national, Michael Yang, as helping set up a drug manufacturing lab in Davao.
Yang has been appointed an economic adviser to the government and has often been seen in the company of Philippines President Rodrigo Duterte, who has faced criticism for the thousands of Filipinos killed in his so-called "war on drugs".
Al Jazeera's Jamela Alindogan reports from Manila.
