MANILA-- Philippine National Police chief Ronald "Bato" dela Rosa on Thursday defended elite police unit Special Action Force (SAF), following a prison riot that left high-profile inmate Tony Co dead and four other inmates injured.

"Hindi natin masasabi na nagkukulang yung ating SAF doon. In fact, I am very proud of them. I'm very happy [with] what they are doing," Dela Rosa said.

"Yun nga lang pag may nangyari--yung nangyari naman na yun ay beyond our control dahil nga sa pagtatago ng mga ganung bagay hindi talaga natin mabubungkal ang buong building," he added.

SAF was ordered to secure the New Bilibid Prisons when President Rodrigo Duterte assumed power. Previously, the Bureau of Jail Management and Penology (BJMP) was in charge of the national penitentiary.

Dela Rosa explained that since SAF officers were deployed in the NBP, inmates had a hard time bringing in contraband. However, police cannot fully remove illegal arms already inside the security compound before SAF deployment.

"Yung mga armas na yun na andun na dati, we cannot accept that inch by inch makakalkal, mabubungkal natin buong lugar na building 14 or yung maximum security compound. Talagang meron silang itatago diyan, hindi natin makalkal or otherwise," he said.

He added that if not for the presence of SAF officers, other inmates would have died.

"Kung hindi mabilis na nagreact yung SAF baka namatay lahat nung sugatan doon pero dahil sa bilis ng reaksyon nila ayun nasave yung buhay nung ibang inmates na nainvolve dun sa riot [SAF swiftly reacted to the incident. If not, more people involved in the riot would have died]," he said.

Convicted crime lord Tony Co was killed, while alleged drug king Jaybee Sebastian was injured along with Vicente Sy, and drug convict Peter Co who is in critical condition.

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Asked whether the incident was a simple prison riot, Dela Rosa said that they are accepting the initial report of the Department of Justice but have also sent the Criminal investigation and Detection group to probe the melee.

"Right now I have sent already the director of CIDG to NBP to coordinate kung pwede CIDG ang magtake-over. As of yesterday pumayag sila na CIDG ang magtake over."

Dela Rosa revealed that he spoke with CIDG Director Benjamin Magalong to bring riot suspects to Camp Crame to give their testimonies. Dela Rosa refused to name the suspects.

"Mahirap kasi magspeculate we must be very careful. Per se, yung initial investigation yun ang tinatanggap natin yung BuCor (Bureau of Corrections)," he said.