Two US service members were killed and two wounded in southern Afghanistan province of Kandahar when their vehicle struck an improvised explosive device, the NATO press office said in a statement.

The US service members were conducting operations as part of the NATO-led Resolute Support Mission. They are the first U.S. military members to be killed in Afghanistan in 2020.

Their names and other biographical information would not release until 24 hours after notification of next of kin, NATO said.

The Taliban took responsibility for the January 11 attack, saying it occurred in the southern Kandahar Province, where U.S. and Romanian forces are stationed.

Around 12,000 US troops are currently serving in Afghanistan as part of a NATO’s Resolute Support training and assistance mission Afghan forces.

There have been more than 2,400 US service members died since the start of America’s longest war in 2001. Last year, 20 U.S. service members died in Afghanistan were the highest in five years.

The Afghan Interior Ministry reported on January 3 that 2,219 civilians were killed and 5,172 were wounded by Taliban militants last year.

The Taliban militants have killed 2,219 civilians and wounded 5,172 others in last year, the Afghan Ministry of Interior said.