MANILA - International non-government organization Human Rights Watch on Friday condemned President Rodrigo's anti-narcotics drive anew following the discovery of a hidden jail for drug suspects in Manila.

"The discovery of the secret jail is just the latest sign of how police are exploiting Duterte's abusive anti-drug campaign for personal gain," HRW said in a statement.

Earlier Thursday, the Commission on Human Rights (CHR) found 12 men and women detained inside a cramped room hidden behind a bookshelf in the Raxabago police station in Tondo, Manila.

CHR said there was no record of the arrest and inquest proceedings for the detainees, who alleged that cops held them in the facility for a week, without notifying their families or lawyers.

The detainees also accused policemen of torturing them and demanding money for their freedom.

They also claimed that inadequate lighting, ventilation, and toilet facilities forced them "to urinate and [do] bowel movements in plastic bags," according to CHR-Metro Manila director Gilbert Boisner.

Mga biktima umano ng 'tokhang for ransom', natagpuan sa Maynila https://t.co/C1WJRk6FrQ pic.twitter.com/kTEoi94CK0

— DZMM TeleRadyo (@DZMMTeleRadyo) April 28, 2017

Supt. Robert Domingo, commander of the Raxabago station, has denied the allegation, insisting instead that those detained in the hidden cell could not mix with other suspects in the station's main cell because no case has been filed against them yet.

Domingo and 12 other officers of the Raxabago station were temporarily relieved to pave the way for an impartial probe.

At least two senators have spoken out against the maintenance of a "secret jail" for drug suspects.

Senator Panfilo Lacson, a former chief of the Philippine National Police, noted: "If true, these policemen are no better than the kidnap-for-ransom gangs that I used to chase throughout my law enforcement career."

"Those responsible must therefore be treated no differently from those criminal syndicates that they themselves are mandated to neutralize."

Sen. Kiko Pangilinan added that the matter should be investigated thoroughly and wrongdoers swiftly punished.

"We have seen how PNP uniformed personnel have in the Jee Ick-Joo case, the Espinosa rubout case, and in a number of other cases abused their office under the guise of the war on drugs. If this systemic pattern of abuse is not addressed, I am afraid the war on drugs will fail in its objective of ridding the nation of illegal drugs and instead succeed in spreading lawlessness, police corruption, and abuse," he said.

ABUSES

HRW noted that policemen at the helm of Duterte's war on drugs have been tagged in a string of alleged abuses over the past months.

Last October, anti-narcotics cops allegedly abducted a South Korean businessman and strangled him to death, before demanding a ransom from his family, the group said.

• 'Kidnapped South Korean was killed by Filipino cops'

HRW added that it has exposed a "damning pattern of unlawful police conduct" in the deaths of over 2,000 drug suspects during police operations.

"Expect unlawful police abuses in the name of Duterte's 'war on drugs' to continue until the United Nations establishes an urgently needed independent, international investigation into the killings and the secret jails that are part of it," HRW said.

Malacañang has maintained that the state is not behind extra-judicial slays, as deaths attributed to the police occurred in legitimate operations.

Duterte also said that his orders to kill and arrest drug suspects come with the caveat that police should operate within the bounds of the law.

The National Capital Region Police Office and the Philippine National Police-Internal Affairs Service will conduct separate probes into Manila's hidden jail.