WASHINGTON — Staff Sgt. Mark R. De Alencar has been identified by the Pentagon as the Green Beret killed Saturday fighting Islamic State in eastern Afghanistan.

The Florida-based soldier died in Nangarhar Province when his unit was attacked by enemy small arms fire during combat operations against ISIS, according to a Pentagon statement Monday. The 37-year-old was assigned to 1st Battalion, 7th Special Forces Group at Eglin Air Force Base. De Alencar was from Edgewood, Maryland.

American forces in Afghanistan are primarily charged with advising and assisting Afghan security forces as part of NATO’s Resolute Support mission, but the U.S. military also conducts counterterrorism combat operations against groups such as ISIS and al-Qaida under its unilateral Freedom’s Sentinel operation.

Pentagon officials have said destroying the ISIS affiliate in Afghanistan is among the top goals for the United States in the country for 2017.

De Alencar recently joined Special Forces as a weapons sergeant after completing the Qualification Course in September 2016, according to Army Special Operations Command. He joined the Army in 2009 and had served previously as an infantryman, including deployments to Iraq.

His awards and decorations included the Ranger Tab, Special Forces Tab, the Purple Heart, Six Army Commendation Medals, Combat Infantryman Badge and Expert Infantryman Badge.

The soldier was a 1998 graduate of Joppatowne High School in Joppa, Maryland. He and his wife Natasha had five children, according to a Facebook page for the high school’s alumni. Several alumni on the page offered condolences to De Alencar’s family and some of them noted he had long sought to join Special Forces.

De Alencar came from a military family, according to Army Special Operations Command. He was born in a military hospital in Germany where his father was stationed. He later lived in Texas before moving to Maryland.

De Alencar was the first American killed in action in Afghanistan in 2017. Ten U.S. servicemembers were killed in hostile situations in Afghanistan in 2016, according to the website icasualties.org, which tracks those numbers. Since U.S. troops first invaded Afghanistan in 2001, 2,217 American have been killed there and some 20,000 more have been wounded in action, according to the Pentagon.

“On behalf of all of U.S. Force -Afghanistan, I offer our deepest condolences to the family and friends of our fallen comrade,” Gen. John Nicholson, the top U.S. commander in Afghanistan, said Saturday in a statement. “We will always remember our fallen comrades and commit ourselves to deliver on their sacrifice.”

The United States and Afghan special forces are battling ISIS in the small portion of Nangarhar Province that the terrorist group still controls. Pentagon officials said ISIS is confined to only a few district centers and has lost nearly half its fighters in Afghanistan in the last year.

dickstein.corey@stripes.com

Twitter: @CDicksteinDC