The number of casualties from the encounter between officers of the Philippine National Police-Special Action Force (PNP-SAF) and elements of the Moro Islamic Liberation Front (MILF) in Mamasapano, Maguindanao has now reached 50.

Senior Superintendent Noel Armilla, PNP director for the Autonomous Region in Muslim Mindanao (ARMM), confirmed the figures Monday morning.

All casualties were said to be from the police force, six of them officials.

Troops from the PNP-SAF were killed in a day-long gun battle against MILF fighters in the village of Tukanalipao early Sunday.

The police officers were conducting operations to serve an arrest warrant on Malaysian bombmaker Zulkifli bin Hir, also known as “Marwan” and Abu Sayyaf member and foreign-trained bombmaker Abdul Bassit Usman.

Meanwhile, the military is still verifying reports that Marwan was killed in the firefight.

In a press briefing at Camp Aguinaldo Monday, Defense Secretary Voltaire Gazmin said that members of the PNP-SAF were able to “neutralize” Marwan but Usman was able to escape.

“Well, we have no confirmation but that was the report we got last night…According to reports they [PNP] were able to neutralize one of them, si Marwan, although ‘yung isa nakawala, ‘yung si Basit Usman, Gazmin said.

In a report to PNP officer-in-charge Deputy Director General Leonardo Espina, SAF director Chief Superintendent Getulio Napenas Jr. said  that SAF operatives were able to “neutralize” Marwan at around 2:30 a.m. on Sunday during the encounter in Barangay Tukanalipao, Mamasapano.

However, Napenas claimed they were not able to extricate Marwan’s body due to the heavy volume of fire coming from the side of the rebel groups.

Gazmin, Espina and Interior and Local Government Secretary Mar Roxas will go to Maguindanao and Cotabato later in the day to assess the situation and to confirm reports on Marwan’s death.

“We will validate that [report]. I am going to Cotabato today so that I can get more accurate information to be able to disseminate to you,” Gazmin said.

Marwan, said to be a top operative of the Jemaah Islamiyah and the man behind the Bangsamoro Islamic Freedom Fighters, is wanted by the US Federal Bureau of Investigation with a $5-million bounty for his capture. He was reportedly killed in 2012, but no body was recovered. He has since resurfaced in Mindanao.