Story updated to include the Metro Manila Police Office's comment on President Duterte's statement.

Metro Manila (CNN Philippines, August 21) — President Rodrigo Duterte said if police are found liable for the killing of 17-year-old alleged drug runner Kian Delos Santos, they will go to jail.

"Should the investigation point to liabilities, by one, two or all, there would be a prosecution, and they would have to go to jail if convicted. That I can assure you, there will be no luto-luto (whitewash) diyan," Duterte said in a press conference in Malacañang late Monday.

"I'm sorry, but you have to face the justice system," he added, referring to the police involved.

Duterte said he will wait for the findings of the National Bureau of Investigation (NBI) into Kian's death.

"The organization (of) PNP is under me. I would be the last person to condemn them without a valid investigation," Duterte said.

Kian was one of the 82 killed in various anti-drug operations in Metro Manila and Bulacan from August 15 to 16, in what was yet one of the deadliest weeks in the government's war on drugs.

The NBI began its investigation on August 18. Justice Secretary Vitaliano Aguirre said the NBI hopes to find out if the 17-year-old Grade 11 student's killing was done "in cold blood."

Read more: Justice Secretary: NBI probe to prove if minor was killed 'in cold blood'

Police officials on Tuesday said Duterte's remarks proved they made the right decision to relieve the police in question and submit them for investigation.

"We welcome anyone who has any additional information and wish to shed light on the case," National Capital Region Police Office Spokesperson Chief Inspector Kim Molitas said.

Duterte added he has already ordered the Philippine National Police Chief Ronald Dela Rosa to find the police officers responsible for Kian's killing.

"Nung nakita ko 'yung (CCTV) tape tinawagan ko si Bato (dela Rosa). Sabi ko, hulihin mo na at ikulong mo," Duterte said, referring to the Caloocan City footage of the incident.

[Translation: When I saw the tape, I called dela Rosa. I told him, arrest and imprison whoever's responsible.]

Related: Albayalde relieves Caloocan City Police chief

CCTV footage Wednesday showed a young man believed to be Delos Santos is being dragged away by two men in civilian clothes.

When Duterte was asked if there is possibility of abuse on the part of police during its anti-drug operations, he answered, "A lot of them are already facing charges in court. Hindi ko mapigilan 'yan [I wouldn't be able to stop it]."

Duterte then warned policemen against committing illegal acts.

"Kayong mga pulis kayo, you will find that you are far much worse than drugs, because you are destroying the credibility of government," Duterte said.

His warning to the police is a rare statement made by a President who has repeatedly said he will protect police from criminal charges as long as they are performing their duties.

Duterte reiterated his two-million-peso reward for each errant officer, with the money coming from intelligence funds.

"Basta may warrant, kidnapping, murder for hire, sa pulis, two million, automatic 'yan," he said. "Alalahanin ninyo, may pamilya kayo. Alam namin kung saan kayo nakatira."

[Translation: As long as there is a warrant, police officers charged with kidnapping or murder for hire will automatically have a P2 million bounty. Remember, you have families. We know where you live.]

The President's reward was earlier announced on police officers who were allegedly working as henchmen for the Parojinog family in Ozamiz City.

Read: Duterte: ₱2M each for cops in cahoots with Parojinogs

Duterte won't visit wake

The President also said he would not visit Delos Santos' wake, saying that Vice President Leni Robredo has already dropped by.

"Good. Sana sinali na lang niya pangalan ko, kasi sa gobyerno naman kaming dalawa," he said.

[Translation: Good. I wish she included my name because we're both from government anyway.]

Robredo visited Kian's wake on Sunday.

Read more: VP Robredo calls for independent probe on Kian's death

Duterte also said a visit to Kian may imply that he is apologizing on behalf of the police.

"I would be putting so much pressure on the police. Mataranta na sila niyan [They'll get paranoid]," he said.

CNN Philippines Digital Producer VJ Bacungan contributed to this report.