Metro Manila (CNN Philippines) — No policeman or civilian has so far come forward to confirm that three police generals under investigation for links to illegal drugs are protectors of drug lords but they have been directed to explain possible lapses they have committed in the anti-drug campaign, a National Police Commission (Napolcom) official said Thursday.

The three senior officers – former Region 6 Director Chief Supt. Bernardo Diaz, Director Joel Pagdilao who headed the National Capital Region Police Office (NCRPO), and former Quezon City Police Director Chief Supt. Edgardo Tinio – have been relieved of their posts after President Rodrigo Duterte named them and two retired officers as top police officials involved in the illegal drug trade.

The three officers as well as retired Deputy Director General Marcelo Garbo and retired Chief Superintendent Vicente Loot have all denied Duterte’s allegations.

Napolcom Vice Chairman Rogelio Casurao said Pagdilao, Diaz and Tinio were asked to explain their side on the “adverse findings” made by investigators, who are gathering evidence against them.

Casurao declined to give details of the results of the investigation but said the three police generals were asked Thursday to respond by next week to their alleged “violations of existing memo circulars” and “disregard of operating procedures.”

“These directives were supposed to check and see to it that the drug problem is taken cared of," Casurao said.

Casurao also said they also will be made to explain why some police officers without proper training were transferred to an anti-illegal drugs unit.

"If the persons assigned to these units have not undergone training, for instance, and they were assigned to these units at the whims and caprices of the appointing authority, then there is reason again to doubt why things happened that way," Casurao said.

Also read: Dela Rosa to send cops involved in drugs to Sulu, Basilan to fight Abu Sayyaf

He said the three senior officers have also failed to submit pre- and post-operational reports on their anti-illegal drugs operations, and the Philippine National Police (PNP) National Headquarters has called their attention to that.

"Kung, halimbawa, [If, for example,] there is really a total disregard of these existing policies, then they are liable administratively," Casurao said.

He said Napolcom investigators also are looking at possible properties belonging to the three officers that are not reflected in their Statements of Assets, Liabilities and Net Worth (SALN).

Casurao said investigators will use documents from the Land Registration Authority and Securities and Exchange Commission to check if there are properties and companies in the names of the officers which they have not disclosed.

If Pagdilao, Diaz and Tinio are unable to provide “compelling justifications” for these lapses, Casurao said they may face administrative cases.

He said investigators have already compiled “voluminous documents” as evidence to back administrative charges.

Casurao has said that investigators have also obtained sworn affidavits from policemen and civilians that will corroborate the documents that they have.

However, none of them confirmed that the three senior officers are protectors of illegal drug operations, he said.