MANILA — Philippine police were knocking on doors in one of Manila’s poorest neighborhoods on Wednesday to encourage people to take on-the-spot drug tests, a campaign condemned by rights groups as harassment that could endanger lives.

Carrying drug testing kits, police officers accompanied by community officials were seen going to houses asking residents if they were willing to submit urine samples.

Payatas, one of the most populated sub-districts, or barangays, in the capital’s Quezon City neighborhood, has been identified as a crime-prone area with a serious drug problem. Community leaders said they requested help from police, and testing was voluntary.

Dozens of Payatas residents have died during President Rodrigo Duterte’s ferocious 14-month-old war on drugs, which has killed thousands of Filipinos, many in what critics say are suspicious circumstances.

Residents say more than 300 of the 130,000 people in Payatas are already on a drug “watch list” drawn up last year by community leaders of known addicts.

Barangay watch lists are drawn up by community leaders to identify those in need of rehabilitation, but activists say some of those who appeared on them have become targets for assassination. The authorities deny the watch lists serve as hit-lists.

On Wednesday, Reuters saw a small number of Payatas residents lining up to be tested but the police did not say how many were found clean or to be drug users. Community leaders did not say what will happen to people who tested positive for drug use or to those who refuse to be tested.

“Our goal is to have a drug-free barangay this year,” Payatas barangay secretary Marlene Ocampo told Reuters, adding the village council agreed to fund and conduct free and voluntary drug testing, which could take four to five months.

“We only asked the police to help us and we are grateful,” she said. “We have more than 133,000 residents.”

She said there were no complaints, and many residents agreed to undergo tests.

“This is also good for us,” said Maria Luisa Valdez, a 37-year-old food vendor. “We are clean. We don’t do drugs so why would be afraid to take the test.”

The head of the National Union of People’s Lawyers, Edre Olalia, said police were on a “fishing expedition” to draw up a list of drug users, and doubted the testing was voluntary.

Meanwhile, Philippine President Rodrigo Duterte on Wednesday backed police on the front lines of a war on drugs that he said would not cease, but warned officers their duty was to arrest suspects and kill only if their lives were in danger.

The firebrand leader, now facing the most intense scrutiny so far in his controversial but popular crackdown, said he could not justify last week’s high-profile killing of a high school student, and police responsible had not followed instructions and would face justice.

Though Duterte stood firmly behind a campaign that has killed thousands of mostly urban poor Filipinos, his remarks were a departure from the bellicose rhetoric that critics say has created a culture of impunity and emboldened police to execute suspects. Police reject that.

“You are not allowed to kill a person that is kneeling down begging for his life. That is murder,” Duterte said in a speech.

“When I say you get him, it includes doing the arresting and then if there is a violent resistance, they (police) have to defend themselves.” — Agencies