MANILA – American authorities have confirmed that one of the terrorists killed five days ago in Marawi City is Isnilon Hapilon, a terror leader wanted in the United States for acts against its nationals and other foreigners.

In a statement Saturday, Defense Secretary Delfin Lorenzana said the Federal Bureau of Investigation (FBI) "has confirmed that the DNA sample taken from a body recovered by our operating units in Marawi matches that of Isnilon Hapilon."

Hapilon was last known as the anointed Islamic State leader in Southeast Asia. The military earlier said the Marawi City firefights ensued in May following government's attempt to arrest him.

Philippine forces killed Hapilon, leader of the Abu Sayyaf Group, and another terror leader Omar Maute in Marawi City earlier this week as government troops inched closer to ending the five-month crisis.

• Terrorists Isnilon Hapilon, Omar Maute killed in Marawi battle

The FBI is also conducting DNA analysis on the cadavers of other terrorists recovered from Marawi, he said.

The US had placed a $5-million (P264.4) reward for Hapilon's head, citing his involvement in terror acts including the abduction and murder of a US national.

The Abu Sayyaf was behind the May 2001 abduction of several tourists at the Dos Palmas Resort in Palawan, where US national Guillermo Sobero was beheaded.

American missionary Martin Burnham, also among the captives, was meanwhile killed during a rescue attempt by the Philippine military in June 2002.

• READ: 2 Abu Sayyaf men held for Dos Palmas kidnappings

One of the FBI's "most wanted" terrorists, Hapilon was indicted in Washington D.C. "for his alleged involvement in terrorist acts against United States nationals and other foreign nationals in and around the Republic of the Philippines."

• Who will get multi-million reward for Hapilon, Maute deaths?

On Monday, Armed Forces Chief of Staff Eduardo Año said, "deserving" informants will undergo a process to claim the reward.

"It will undergo a process. Meron tayong mga informants na qualified and deserving to receive the reward. Susundan natin 'yung proseso na naayon doon sa US reward claim system," he said in a press conference.

In June, President Rodrigo Duterte offered a separate P10 million reward for the "neutralization" of Hapilon, and P5 million each for brothers Abdullah and Omar Maute.

Following the killing of Hapilon and Omar Maute, President Rodrigo Duterte on Tuesday declared that Marawi City had been "liberated from terrorist influence."

State troops continue to close in on remnants of terrorist forces, who are known to still be holding several hostages in a half-hectare area in Marawi City.