Four Philippine policemen were found guilty Tuesday of killing a father and son, court officials said, in a rare case of law enforcement officers being prosecuted for taking part in former president Rodrigo Duterte's deadly drug war.

The four low-ranking officers were all sentenced to up to 10 years in prison for the shooting deaths of the two victims at a Manila slum during an anti-drug police operation in 2016, Manila regional trial court judge Rowena Alejandria said in her written verdict that was read in court Tuesday.

"It must be worthy to note that the accused themselves did not deny their presence and participation in the police operation conducted, the same event where the victims Luis and Gabriel (Domingo) were killed," Alejandria wrote.

Thousands of drug suspects were killed by police and unknown gunmen in a campaign that became the centrepiece of Duterte's 2016-2022 rule, a crackdown that critics described as state-sponsored extrajudicial killings and is now a subject of an investigation by the International Criminal Court.

Luis Bonifacio's partner, Mary Ann Domingo, cried on her son's shoulder as they listened to the verdict on two counts of homicide each being read at the cramped northern Manila courtroom.

Manila policemen Virgilio Cervantes, Arnel de Guzman, Johnston Alacre and Artemio Saguros were also ordered to pay 300,000 pesos ($5,120) each in damages to the victims' heirs.

The family has alleged more than a dozen police officers took part in the nighttime raid at the northern Manila slum community.

The family insisted the two were not involved in drugs and were unarmed when police opened fire.

The defendants pleaded self-defence, alleging the suspects were armed and had shot at them.

But state prosecutors went with the lesser charge of homicide against only four officers, instead of murder, which involves deliberate intent to kill and which carries a heavier penalty.

- ICC investigation -

Official data shows more than 6,000 people died in police anti-narcotics operations.

But rights groups estimate tens of thousands of mostly poor men have been killed by officers and vigilantes, even without proof they were linked to drugs.

Duterte had openly ordered police to shoot dead suspects during anti-drug operations if officers believed their lives were in danger.

While the crackdown has been widely condemned and sparked an international investigation, only five other policemen have been convicted for killing drug suspects.

Three Manila police officers were convicted in 2018 of murdering a 17-year old boy in 2017. Two other narcotics police officers were found guilty last year for separate killings in 2016 and 2017, the latter victim a South Korean businessman.

Lawyers say most families are too scared to go after their relatives' killers or do not have the money or time to pursue a case in the Philippines' creaky judicial system.

The Philippine drug crackdown is being investigated by the International Criminal Court, which said in 2021 that it appeared "a widespread and systematic attack against the civilian population took place pursuant to or in furtherance of a state policy".

Duterte pulled the Philippines out of the ICC in 2019, so only cases before that date are covered by the investigation.

President Ferdinand Marcos, who succeeded Duterte, has refused to cooperate in the ICC probe, saying Manila has a functioning judicial system.

AFP

Mary Ann Domingo and her younger son hold portraits of her husband and son after four policemen were found guilty of killing them during an anti-drug raid © Ted ALJIBE / AFP

Court finds four Philippine police guilty in drug war killings