Amid a United Nations investigation into a brutal "war on drugs" by Philippine president Rodrigo Duterte, a Catholic bishop is calling for the country's Department of Health (DOH) to take a more active health-centered approach to tackling the nation's drug problem.

Bishop Pablo Virgilio David of Kalookan, a city in metro Manila, said this week that intimidation and killings will not stop the problem of drugs in the country.

"I've been challenging the DOH to be more involved in drug rehabilitation because drug addiction is a mental health issue," he said, according to Catholic Bishops Conference of the Philippines (CBCP) News.

David is a vocal critic of Duterte's harsh tactics against drug users and dealers, and the government's tactics have been a major point of contention with Catholic leaders for several years.

In 2017, the country's bishops called for both a 33-day rosary campaign and a 40-day prayer campaign for peace.

Over the past three years, Duterte has been heading a brutal war on drugs in the Philippines. The campaign against drugs has drawn significant international criticism for its reported extrajudicial killings and death squads. Nearly 500 deaths have been reported this year alone, and more than 6,000 people were killed in the six months after he took office.

By the beginning of 2017 alone, police reported at least 2,250 drug suspects killed, while at least 3,700 others were murdered by unknown suspects who sometimes accused their victims of being drug dealers or addicts, according to AFP.

Human rights organizations now put the total death toll since 2016 at more than 27,000- a figure that includes those killed by vigilantes, Rappler reports.

Jerome Secillano, public affairs chief for the Catholic Bishops Conference of the Philippines, has said that many priests and bishops, as well as Catholic laity, are afraid to speak out against the killings.

Duterte made the war on drugs a major part of his 2016 political campaign, and continues to enjoy high levels of approval in the Philippines.

In July 2019, the UN Human Rights Council narrowly approved a resolution to launch an investigation into the drug war. The resolution does not go as far as to create a full commission to examine the matter, but instead authorizes an investigation to examine alleged crimes against humanity, including reports of extrajudicial killings, disappearances, and arbitrary arrests.

Michelle Bachelet, the UN's High Commissioner for Human Rights, will present the findings in a report next year.

Bishop David said he is also concerned about an increase in suicide, and stressed the need for the government to give more attention to mental health problems in the country, CBCP News reports. According to the country's DOH, some 3.3 million Filipinos suffer from depressive disorders.