The number of dead suspects Tuesday is the highest the province has seen in a single night, Caramat said. He referred to the night of police action as a "one-time, big-time" operation, indicating that it was targeting "notorious drug pushers."

In addition to the 32 killed, 107 persons were arrested, he added.

"Some quarters of the society are questioning why that many ended up dead, but all we can say is that we don't have any control of the situation," Caramat added.

"These subjects in this one time big-time operations, they are what we call the notorious drug pushers. They are called notorious. They won't let themselves be arrested alive."

Uncontrollable problem?

Prior to Tuesday's police operation, Bulacan provincial police disclosures show at least 14 drug suspects died in separate police operations over the course of the month.

In July, at least 18 suspects were recorded dead in drug-related operations in the province.

Last week, Duterte said that his administration "can't control" the country's drug problem.

He suggested that his government didn't have the resources, and the problem was exacerbated by the country's huge coastline -- the Philippines is comprised of over 7,000 islands.

He pledged to resign after six months if he had not fixed the drug problem, but later backed away from that promise.

According to Philippines government data, more than 3,400 suspects have been killed in police operations since July.

Local and international human rights groups claim more than 9,000 people -- including vigilante killings and those killed in police operations -- have died as a result of the drug war.