The Defense Department has identified two U.S. service members and a Defense Department civilian, who were killed by an ISIS suicide bomber Wednesday in Manbij, Syria. A Defense Department contractor was also killed in the blast.

Army Chief Warrant Officer 2 Jonathan R. Farmer, Navy Chief Cryptologic Technician (Interpretive) Shannon M. Kent, and Defense Department civilian Scott A. Wirtz were killed, a Pentagon news release says.

Farmer, 37, was assigned to 3rd Battalion, 5th Special Forces Group (Airborne) at Fort Campbell, Kentucky. He joined the Army in 2005 and was on his sixth combat tour, a U.S. Army Special Operations Command news release says. He deployed to Iraq five times and to Afghanistan once. His military awards include the Bronze Star with two Oak Leaf Clusters and Purple Heart.

He is survived by his wife and four children, the news release says.

Kent, 35, was assigned to Cryptologic Warfare Activity 66, based at Fort George G. Meade, Maryland. She joined the Navy in 2003 and became a chief petty officer in August 2012, according to her military record. Her military awards include the Iraq Campaign Medal, Rifle Marksmanship Ribbon, and Pistol Marksmanship ribbon.

“Our thoughts and prayers go out to the family, friends, and teammates of Chief Petty Officer Kent during this extremely difficult time. She was a rock star, an outstanding chief petty officer, and leader to many in the Navy Information Warfare Community,” Cmdr. Joseph Harrison, Commanding Officer of Cryptologic Warfare Activity 66, said in a news release.

Wirtz was assigned to the Defense Intelligence Agency as an operations support specialist. He is a former SEAL, who spent 10 years in the Navy, leaving the service as a petty officer first class, according to his DIA biography. He joined the DIA in February 2017 and made three deployments to the Middle East with the agency.

Defense officials have not released much information about the circumstances surrounding their deaths. Army Col. Sean Ryan, a spokesman for the U.S. military in Iraq and Syria, said all four Americans were “conducting a routine patrol in Syria” when the explosion occurred.

President Donald Trump and Vice President Mike Pence paid tribute to the four Americans killed while speaking Thursday at the Pentagon.

“I want to take a moment to express my deepest condolences to the families of the brave American heroes who laid down their lives yesterday in selfless service to our nation – these are great people; great, great people.” Trump said. “We will never forget their noble and immortal sacrifice.”

Trump has ordered the withdrawal of all U.S. troops in Syria, but is unclear how long that will take.

“Today, along with all of you, our hearts and our prayers are with the families of the fallen American heroes who were lost in Syria yesterday as well as those service members who were wounded,” Pence said Thursday at the Pentagon. “We honor their service and we will honor the memory of the fallen.

“Their families and our armed forces should know: Their sacrifice will only steel our resolve that as we begin to bring our troops home we will do so in a way that ensures that the remnants of ISIS will never be able to reestablish their evil and murderous caliphate.”

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