The Philippine government on Saturday warned of ‘malignant elements’ out to sabotage President Rodrigo Duterte's campaign against illegal drugs amid public outrage over the recent killings of three teenagers.

The boys, aged between 14 years and 19 years, were killed in alleged police operations linked to the anti-drug crackdown last month. At least one of them was found with 30 stab wounds and his head wrapped in plastic and tape.

Presidential spokesman Ernesto Abella said the teens' killings, which the government has condemned and ordered investigated, ‘should be viewed with suspicion and urgency.’  ‘The president's campaign against illegal drugs has adversely affected many, including powerful narco-politicians and deep-pocketed drug lords who flourished prior to this administration,’ Abella said.

‘It should not come as a surprise that these malignant elements would conspire to sabotage the president's campaign to rid the Philippines of illegal drugs and criminality,’ he added.

Those adversely affected by the drug war could be taking efforts to discredit the campaign by ‘creating scenarios stoking public anger against the government,’ Abella said.

Human Rights Watch said the teens' killings make it crucial for the United Nations to investigate the campaign and to step up pressure on the Duterte administration for it to stop alleged instigation of drug war killings.

‘Until Duterte ends his abusive drug war and allows a UN-led international probe, child-killers among the police will continue to get away with murder,’ warned Phelim Kine, deputy Asia director at HRW.

More than 3,000 people have been killed in police operations against drug suspects since Duterte came into office on June 30, 2016. Police said those killed fought back when arrested.

Aside from those killed in police operations, authorities also are investigating the deaths of nearly 11,000 other people to determine if their killings were related to illegal drugs and carried out by hired or vigilante killers.

At least two of the three teenagers killed last month - 14-year-old Reynaldo De Guzman and 17-year-old Kian Loyd Delos Santos - appear to have been ‘deliberately targeted’ by the police, according to HRW, which investigates allegations of human rights abuses worldwide.

‘The apparent willingness of Philippine police to deliberately target children for execution marks an appalling new level of depravity in this so-called drug war,’ Kine said.

‘These killings demonstrate that Duterte's rejection of the rule of law has made all Filipinos potential 'drug-war' victims, no matter how young,’ he added.

De Guzman went missing with 19-year-old Carl Arnaiz on August 17 when they went out at night for snacks near their homes in the Manila suburban city of Caloocan.

Arnaiz's body was identified 10 days later in a morgue in Caloocan City. He was allegedly involved in a shootout with police officers who tried to arrest him after he was accused of robbing a taxi driver, a police report said.

De Guzman's body was found on Tuesday in a river in Gapan City in the province of Nueva Ecija, 77 kilometres north of Manila.

On August 16, 17-year-old Kian Loyd Delos Santos was shot dead by police officers who claimed the high school student opened fire at them when they accosted him for alleged involvement in illegal drugs.

The National Bureau of Investigation has been directed to investigate the killings of the three teenagers. A criminal complaint has been filed against three police officers allegedly involved in the killing of Delos Santos. 

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