The president of the Philippines Rodrigo Duterte is carrying out a “large-scale murdering enterprise” and should be investigated by the UN for crimes against humanity, according to a new Amnesty report into his so-called war on drugs.

It has been three years since Duterte pledged to wipe out drug abuse in the Philippines by giving police unprecedented powers and near total impunity to kill any suspected drug addicts or dealers. Amnesty’s new report detailed how the systematic killing of the urban poor has continued on such a scale it now amounts to crimes against humanity.

The report told of nightly incidents where police would shoot defenceless suspects, or abduct them and take them to other locations where they would be shot. It found crime scenes were tampered with, evidence fabricated or planted and there was no accountability for the killing of suspects.

According to the report, local officials were put under huge pressure by police to come up with vast numbers of names to put on the “drugs watch list” without needing to provide any evidence they were using or selling drugs and without any legal process.

Interviews by Amnesty told harrowing stories of figures such as Jovan Magtanong, a 30-year-old father of three, who was shot and killed by police when he was sleeping next to his children. Police had been looking for another man. Officers later claimed he had drugs and a gun on him, which witnesses refuted. “They killed him like an animal”, a family member told Amnesty.

The Amnesty report also highlighted how Bulacan province, in the central Luzon area, had overtaken the capital Metro Manila as the “the country’s bloodiest killing field” in the drugs war.

Relatives of victims in President Rodrigo Duterte’s so-called war on drugs hold a memorial for their loved ones in Manila Photograph: Bullit Marquez/AP

This recent geographical shift was highlighted in recent analysis by the armed conflict location and event data project, which found that the highest proportion of this year’s civilian drug war deaths deaths – almost 25% of the 490 people killed – had happened in the Central Luzon area. This has been attributed to a shift in focus, and police personnel, to the region and a subsequent rise in violent drug raids.

Amnesty called on the UN Human Rights Council to open an independent inquiry to “put an end to these crimes, and to provide justice and reparations for countless families and victims”. It followed a draft resolution drawn up last week by more than a dozen countries formally calling on the United Nations human rights council to open an investigation into the war on drugs.

Nicholas Bequelin, Amnesty International’s regional director for east and southeast Asia, described the war on drugs over the past three years as “nothing but a large-scale murdering enterprise for which the poor continue to pay the highest price,” pointing out that it took nothing but a rumour of association with drugs for people in poor communities to be shot and killed by police without impunity.

“Fear has now spread deep into the social fabric of society,” said Bequelin. “It is time for the United Nations, starting with its Human Rights Council, to act decisively to hold President Duterte and his government accountable.”

The international criminal court (ICC) is currently carrying out its own preliminary inquiry into whether the deaths in Duterte’s drug war, beginning when he was mayor of the Philippine city of Davao in 1988, constitute crimes against humanity, the first investigation the court has done into a southeast Asian country.

The ICC defines crimes against humanity as “serious violations committed as part of a large-scale attack against any civilian population”.

The announcement of the inquiry enraged Duterte so much that he withdrew the Philippines from the Rome Statute, which gives the ICC jurisdiction over the country, but the court is still continuing its investigations.