MANILA -- The International Criminal Court (ICC) should proceed with its investigation on alleged crimes against humanity that have been committed in the Philippines, a human rights group said Wednesday.

Human Rights Watch said the Philippines has yet to respond to their letter asking for details about the government’s claim that it was investigating police involvement in the killings.

“The Philippine government’s request for the International Criminal Court prosecutor to defer its investigation while the authorities conduct their own is a transparent delaying tactic to protect officials responsible for mass killings,” said Human Rights Watch Asia director Brad Adams.

“The ICC prosecutor should seek to resume its official investigation so that justice for victims isn’t further delayed.”

The Office of the Prosecutor of the ICC in November said it suspended its investigation into the alleged "crimes against humanity" committed during the Duterte administration's bloody war on drugs "while it assesses the scope and effect of the deferral request" of the Philippine government."

• ICC Prosecutor suspends probe into PH drug war killings

The announcement came after Philippine Ambassador to the Netherlands J. Eduardo Malaya wrote to ICC Prosecutor Karim Khan asking the international tribunal to defer to the government's investigation of the drug war, noting the mechanisms in place that would assure them of the government's "[commitment] to the rule of law with the highest regard to due process."

• ICC suspension of PH drug war probe 'part of due process'— advocates

At least two lawyers' groups have questioned the deferral of the probe, casting doubt on the probe the Philippine authorities are conducting.

• FLAG asks ICC to lift suspension on probe on PH drug war killings

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