ZAMBOANGA CITY, Philippines — Education Secretary Leonor Briones said the department is working to address isolated cases of teachers being involved in illegal drugs but said she would not allow them to undergo "tokhang" — the codename for the government campaign against drugs.

Briones, in a press briefing in Zamboanga City, said she is concerned at the possibility of public school teachers in the drug trade after one was arrested in an anti-drug operation in the city.

She said the Department of Education is working very closely with the Philippine Drug Enforcement Agency and that a drug testing program is ongoing to screen teachers.

READ: Teacher, 16 others held for drugs

"But there will be no tokhang. We do not support this tokhang tokhang. Even if you torture me, I will not tell you where the findings are and I'm the only one who knows them anyway," she said.

Tokhang originally referred to "toktok-hangyo" or "knock and plead", where authorities visit drug suspects in their homes to convince them to surrender or to enter rehabilitation programs. It has also come to mean extrajudicial killings that critics of the narcotics crackdown link to the campaign.

She said that results of the drug testing will be dealt with internally.

A teacher who tests positive will have to go through confirmatory testing and assessment to see if they can still be rehabilitated.

Those found positive will need to go on leave and go through treatment. They will not be allowed to return until a qualified professional clears them to go back to teaching.