MANILA - The justice chief on Saturday called for the cooperation of the country's police force and anti-narcotics agency as the National Bureau of Investigation (NBI) has been directed to solely handle and give "highest priority" to the investigation of the deadly shootout between the two law enforcement agencies.

In a statement, Justice Secretary Menardo Guevarra said President Rodrigo Duterte told Philippine National Police chief Gen. Debold Sinas and Philippine Drug Enforcement Agency Director General Wilkins Villanueva on Friday to halt their joint investigation on the Feb. 24 "misencounter."

Four were killed- two police officers, an agent and an informant- and four were wounded in the shootout on a parking lot near a mall on busy Commonwealth Avenue on Wednesday.

PNP and PDEA officials have yet to explain how the gunfight between the two law enforcement agencies happened, drawing questions and public criticism on their engagement protocol.

"He (Duterte) reiterated his order to the NBI to assume the sole responsibility of conducting an independent and impartial probe. I requested that both the PDEA and the PNP be directed to extend their full cooperation to the NBI," Gueverra, whose office oversees the NBI, said in a statement.

"I have directed the NBI to give this investigation the highest priority in view of the public interest that the subject incident has generated and its impact on the government's campaign against illegal drugs," he said.

Malacañang earlier said the President has ordered that only the NBI should probe the incident "to ensure impartiality."

• READ: House probe sought in QC shootout between police, drug agents

House Committee on Dangerous Drugs Chairman Rep. Ace Barbers, meanwhile, announced the suspension of his panel's probe on the matter following the development.

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Barbers this week said the inquiry wanted to find out if the incident had stemmed from a "sell-bust," which is illegal.

• READ: No 'sell-bust' in Quezon City shootout, PDEA chief says

A fuming Villanueva already denied this, and said sell-busts are not part of the PDEA's illegal drug operations. He also emphasized that the operations were legitimate.

"Wala naman sa pre-operation or anti-drug operation ang sell-bust dahil bawal 'yan. Buy-bust ang PNP, buy-bust ang PDEA," he said in a presser on Thursday.

Duterte has since vowed justice for those killed in the shootout, which involved two organizations leading his anti-drug campaign.

• Palace: Duterte says 'justice will be done' in PDEA-PNP shootout

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