MANILA — The Philippine Drug Enforcement Agency (PDEA) is now investigating the arrest of anti-drug officers in its Taguig office following a buy-bust operation there on Tuesday.

"PDEA is doing an internal investigation to get to the bottom of the case and determine the ones culpable," the agency said in a statement Wednesday.

Tuesday's buy-bust operation by local police inside the PDEA Southern District Office in Brgy. Upper Bicutan led to the arrest of its chief and other personnel.

The National Capital Region Police Office had seized packets of suspected shabu worth P9 million.

PDEA Director General Moro Virgilio Lazo earlier expressed dismay over the incident.

"Unfortunately, this thing happened," he said.

The suspects were active PDEA agents at the time of the drug sting, said Brig. Gen. Kirby Kraft, Southern Police District's chief.

The PDEA, in the statement, said it is beefing up its internal counterintelligence efforts within its ranks "to preserve the agency's integrity and moral ascendancy to serve the public."

It added that the PDEA and the Philippine National Police had agreed to strengthen their collaborative efforts following the case.

"The operation was properly coordinated with PDEA, an indispensable requirement before drug law enforcement units can carry out anti-drug operations," it also said.

• Death toll in PNP-PDEA shootout rises to 4

—with a report from Nico Bagsic, ABS-CBN News

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