Drug lords could be using the human rights groups to discredit President Rodrigo Duterte's administration, an official said on Monday.

In a statement, Presidential Spokesperson Harry Roque cited that the attacks against government's war on drugs have been "vicious and non-stop."

"We therefore do not discount the possibility that some human rights groups have become unwitting tools of drug lords to hinder the strides made by the Administration," he said.

Roque noted that the illegal drug trade is a multi-billion peso industry as he estimated that billions of money have been lost with the voluntary surrender of more than a million drug users in the country.

He cited the arrest of tens of thousands of drug personalities and seizure of billion-peso clandestine drug laboratories and factories in the Philippines.

"To continue to do and thrive in the drug business, these drug lords can easily use their drug money to fund destabilization efforts against the government," the spokesman added.

Since Duterte assumed office in June 2016, he declared war against illegal drugs.

According to the official data of the Philippine National Police, over 4,000 drug personalities have been killed after they allegedly resisted arrests.

But some quarters have said the number of deaths due to the war on drugs as even higher than the official record.

The alleged extrajudicial killings in the country drew attention of the local and international human rights groups.

Criticisms by some United Nations officials and the preliminary examination being conducted against the President by the prosecutor of the International Criminal Court prompted Duterte to order the country's withdrawal from the Rome Statute, creating the ICC.

Duterte has been charged before the ICC by a Filipino lawyer, with the backing of two Filipino opposition lawmakers, for alleged crimes against humanity due to his bloody war on drugs. Celerina Monte/DMS