Thompson, 28, of Irvine, Calif., was assigned to 3rd Battalion, 1st Special Forces group, according to an Army release. The incident is under investigation.
“He was an exceptional Green Beret, a cherished teammate, and devoted husband. His service in Afghanistan and Iraq speak to his level of dedication, courage, and commitment to something greater than himself,” said Lt. Col. Kevin M. Trujillo, the commander of the U.S. Special Operations task force in Afghanistan.
According to the Army release, Thompson enlisted in the Army in 2011 and reported as a medical sergeant to 1st Special Forces Group in 2014. He was on his first stint in Afghanistan when he was killed and had previously deployed to Iraq in support of the U.S.-led war against the Islamic State there.
Thompson was posthumously awarded the Purple Heart, a Bronze Star with a V for valor in combat and the Combat Infantry Badge.
Helmand province has been the site of heavy fighting in recent weeks as Taliban forces have used the summer months to launch multiple offensives across the country. The group is estimated to control well over 50 percent of Helmand, and its pressure on the provincial capital has forced U.S. and NATO troops to shuttle resources to help prop up the embattled Afghan security forces. Despite their gains around the periphery of Lashkar Gah, the Taliban has been unable to enter the city limits in the face of near-constant U.S. and coalition airstrikes.
On Monday, the NATO-led mission announced that 100 U.S. troops had been moved to Lashkar Gah to primarily advise Afghan police in the area.
Col. Mike Lawhorn, a spokesman for U.S. forces in Afghanistan, said Thompson was not a part of the 100-troop detachment. U.S. Special Operations forces have been operating in and around the city since the Taliban began its offensive in the province earlier this summer.
Thompson’s death marks the second combat death in Afghanistan this year. In January, Army Special Forces Staff Sgt. Matthew McClintock was killed in a pitched firefight alongside Afghan commandos in Marjah, a city in a fertile area just west of Lashkar Gah.
Helmand province, known as the birthplace of the Taliban and nicknamed Marine-istan following President Obama’s 2009 surge into the country, is an opium-rich area that has been the scene of some of the most intense fighting of the nearly 15-year-old war.
While conflict continues unabated in Helmand province, Taliban forces have also recently made gains in the northern part of the country. In the last few days, Kunduz — the city that briefly fell to the Taliban in October 2015 — has been the site of combat between Afghan security forces and the Taliban.
U.S. helicopter gunships and the small prop-driven aircraft of the fledgling Afghan air force have since helped repulse attacks on the city, and officials from the NATO-led mission were optimistic that the Afghan forces would be able to hold their ground.