(UPDATED) The United States is supporting the Philippines' counter-terrorism efforts, White House Press Secretary Sean Spicer said in a statement on Thursday.
"The United States is a proud ally of the Philippines, and we will continue to work with the Philippines to address shared threats to the peace and security of our countries," Spicer said in a statement.
He added that the U.S. condemns the "recent violence perpetrated by an ISIS-linked terrorist group in the southern Philippines."
"These cowardly terrorists killed Philippine law enforcement officials and endangered the lives of innocent citizens," it said.
The U.S. envoy to Manila expressed the same sentiment on Thursday, as government troops continue operations against extremists in the southern city of Marawi.
"As a proud ally, the U.S. will continue to provide support for PH counterterrorism efforts," United States Ambassador Sung Kim said in a Twitter post.
The United States and the Philippines have long been defense allies, with the Mutual Defense Treaty (MDT) inked back in 1951 and the Visiting Forces Agreement (VFA) in 1998. Three years ago, the two countries also signed the Enhanced Defense Cooperation Agreement (EDCA).
Kim's statement came as state forces battled with Maute Group in the southern city of Marawi.
The U.S. ambassador also expressed sympathies for families affected by the attack.
"Concerned about the continued violence in Marawi. My condolences to the families and loved ones of the victims," he said in a separate Twitter post.
The military said it sought the arrest of Isnilon Hapilon, supposedly the designated head of the Islamic State in Southeast Asia.
Clashes erupted on Tuesday as members of the Maute Group and Abu Sayyaf torched several buildings and battled state forces in Marawi, a move which analysts said was meant to divert the military's attention from arresting Hapilon.
Seven government troopers and 13 Maute fighters were allegedly killed in Tuesday's encounter.
On the same day, President Rodrigo Duterte placed the entire Mindanao group of islands under martial law.
On Thursday, the military launched surgical air strikes in three barangays in Marawi City to "flush out" members of the terrorist group, including Hapilon.