Updated

A U.S. solider was killed in combat in eastern Afghanistan on New Year’s Day -- the first such death in 2018 the military has announced.

Four other U.S. service members were wounded during a “combat engagement” in Achin, Nangarhar province, officials said Tuesday. Two were in stable condition and the two others returned to duty.

"We are deeply saddened by the loss of one of our own,” General John Nicholson, commander of the U.S. Forces-Afghanistan, said in a news release. "At this very difficult time our heartfelt sympathies go out to the families and friends of our fallen and wounded brothers."

The name of the soldier has not been released pending family notification.

The United States formally concluded its combat mission in Afghanistan at the end of 2014 but still carries out operations against the Taliban and an ISIS affiliate, both of which are active in Nangarhar.

Vice President Pence made an unannounced trip to Afghanistan just before the Christmas holiday and thanked troops for their service while reiterating the “real progress” the U.S. is making in the country to “put the Taliban on the offensive.”

“I believe victory is closer than ever before,” Pence said. “I believe with all my heart that Afghanistan will be free.”

The Associated Press contributed to this report.