WASHINGTON (AP) — On Monday, officials identified the two Iowa National Guard soldiers who lost their lives in a recent attack in Syria, an assault the U.S. military attributes to the Islamic State group.

The U.S. Army announced the deceased as Sgt. Edgar Brian Torres-Tovar, aged 25, from Des Moines, and Sgt. William Nathaniel Howard, aged 29, from Marshalltown.

In response, Iowa’s Governor Kim Reynolds has directed that all flags in the state be flown at half-staff to honor their sacrifice, expressing gratitude for their service while lamenting the profound loss.

According to Sean Parnell, the Pentagon’s chief spokesperson, a civilian working as a U.S. interpreter was also among the casualties. The Iowa National Guard reported that three additional Guard members sustained injuries, with two now in stable condition and the third in good health.

This attack poses a significant challenge to the improving relations between the United States and Syria following the removal of authoritarian leader Bashar Assad a year prior. The U.S. military is currently enhancing its collaboration with Syrian security forces, with several hundred American troops stationed in eastern Syria as part of a coalition aimed at combating IS.

The shooting Saturday in the Syrian desert near the historic city of Palmyra also wounded members of the country’s security forces and killed the gunman. The assailant had joined Syria’s internal security forces as a base security guard two months ago and recently was reassigned amid suspicions that he might be affiliated with IS, a Syrian official said.

The man stormed a meeting between U.S. and Syrian security officials who were having lunch together and opened fire after clashing with Syrian guards, Interior Ministry spokesperson Nour al-Din al-Baba said Sunday.

Al-Baba acknowledged that the incident was “a major security breach” but said that in the year since Assad’s fall, “there have been many more successes than failures” by security forces.

The Army said Monday that the incident is under investigation, but military officials have blamed the attack on an IS member.

President Donald Trump said over the weekend that “there will be very serious retaliation” for the attack and that Syrian President Ahmed al-Sharaa was “devastated by what happened,” stressing that Syria was fighting alongside U.S. troops.

Trump welcomed al-Sharaa, who led the lightning insurgency that toppled Assad’s rule, to the White House for a historic meeting last month.

Torres-Tovar and Howard were dedicated soldiers and “cherished members” of the Iowa National Guard family, Stephen Osborn, adjutant general, said in a statement.

“Our focus now is providing unwavering support to their families through this unimaginable time and ensuring the legacy of these two heroes is never forgotten,” Osborn said.

Howard remembered as first in, last out

Howard had wanted to be a soldier since he was a young boy, according to Jeffrey Bunn, Howard’s stepfather and chief of the Meskwaki Nation Police Department in Tama, Iowa, about 60 miles (97 kilometers) northeast of Des Moines. Howard “loved what he was doing and would be the first in and last out,” Bunn wrote late Saturday in a post on the police department’s Facebook page.

Howard also was a loving husband and an “amazing man of faith,” Bunn said, adding that Howard’s younger brother, a staff sergeant in the Iowa Guard, would escort “Nate” back to Iowa.

Howard was inspired by his grandfather’s service and wanted to serve for 20 years, according to an April post on a Facebook page dedicated to sharing stories of the unit. He had already served for over 11 years.

Howard “wants his battle buddies to know he’s always there,” the post said, “whether to help or simply listen.”