Special Operations Forces from the United States are helping the Philippine military kick ISIS militants out of a southern town. News of the technical assistance from the United States comes at a time when the local forces suffered its biggest one-day loss on Friday, when 13 marines were killed. The local troops are having a hard time ending the three-week siege of Marawi City, where an estimated 200 militants have taken positions in a corner of the town where an estimated 500 to 1,000 civilians are trapped.

The Philippines military emphasized the United States is providing technical assistance, and not boots on the ground, in the country. The U.S. embassy confirmed the technical assistance on Saturday but didn’t give any details, saying it couldn’t give specifics on American operations for “security reasons.” An Associated Press journalist spotted a U.S. Navy P3 Orion surveillance plane hovering above Marawi on Friday. “We don’t have adequate surveillance equipment, so we asked the U.S. military for assistance. It’s noncombat assistance,” military spokesman Brig. Gen. Restituto Padilla said.

The U.S. involvement in the Philippine fight is seen as particularly significant because it comes a few months after President Rodrigo Duterte threatened to kick U.S. military personnel out of the country amid tensions with Washington over his deadly drug war that has killed thousands of people. But under President Donald Trump, relations with Duterte have been markedly friendlier. In a phone call in May, Trump complimented Duterte on the “unbelievable job” he was doing running the country and his fight against illegal drugs. Trump also invited Duterte to visit him at the White House.