The official gave no details of the United States involvement, but a USA surveillance plan was see flying over Marawi on Friday.
The Philippine military today said that thirteen of its marines were killed on Friday in fierce gun battles with Islamist militants who have laid siege to southern Marawi city for almost a month now.
"They are not fighting".
A U.S. Navy aircraft provided surveillance for the local troops as the battle raged in Marawi on Friday, confirming the involvement of the U.S. military in helping quell the urban insurrection at the request of the Philippine government, Philippine military officials said.
"We don't have adequate surveillance equipment, so we asked the USA military for assistance".
Ties between the United States and the Philippines have been strained since President Rodrigo Duterte took office in June past year.
The American forces were deployed at the request of the Philippines to help defeat Abu Sayyaf, military officials added. Portions of the only Islamic city in the country are falling into debris after successive aerial bombardments of the government forces against its enemies ensued running for several weeks now, but the government said they are now planning on rehabilitation and recovery.
The Islamic State eyed the Philippines as a base for operations after failing to gain a foothold in Indonesia, a Singaporean security affairs analyst said.
In a televised press conference earlier on Saturday, Herrera said that 13 Philippine marines had been killed in battles with some 200 insurgents allied to the "Islamic State" (IS) militant group.
Arevalo, chief military information officer, said the big casualties stemmed from a major engagement that lasted for 14 hours in Barangay Liot Madaya on Friday.
CHR said the call is in consonance with the call of church, local leaders, and other sectors to prevent further damage to lives and properties in the affected communities.
Fahad is married to Rasmia, niece of the captured Maute matriarch Ominta Romato "Farhana" Maute whose sons were involved in the armed skirmishes in the country's south.
Farhana was nabbed along with two wounded Maute fighters after their vehicles were intercepted in the town of Masiu, Lanao del Sur - some 36 kilometers from the warzone - ARMM Regional Police Director Reuben Theodore Sindac was quoted by ABS-CBN news as saying. Herrera also said there are "strong indications" that Omarkhayam and Madie Maute, two leaders of the Marawi attack, were killed in separate operations.
Until now there had been no confirmation that the Philippines had sought US support in the battle for Marawi City on the island of Mindanao, which is in its third week.