Three US service members were killed in Afghanistan Monday when a bomb exploded outside Bagram Air Base, US military officials said.
Three other service members were also wounded when the improvised explosive device detonated on the side of the road.
Military officials on Monday said that a contractor was also killed in the bombing. In a statement on Tuesday, the US Central Command said that the contractor, who had been initially reported as killed, was alive.
The contractor was an Afghan citizen who was initially treated along with other injured civilians. After he was identified as a contractor, he was treated at Bagram Airfield, the statement said.
The device exploded during a military patrol near Ghazni, which has been unstable since Taliban soldiers overran the city in a siege in August, the Washington Post reported.
Citing a spokesperson for the Ghazni governor's office, the Post reported a military operation by Afghan and NATO troops was also taking place in a village southeast of the city at the time.
Military officials said the wounded soldiers were evacuated and are receiving medical care.
The names of the deceased service members are being withheld for 24 hours, per Defense Department policy.
Two US service members were also killed in an operation in March during a joint operation. A US Army Ranger was killed in November by accident by an Afghan commando during a raid on a compound.
Thirteen service members have been killed in Afghanistan this year so far, according to the Post.
The attack came as US and Taliban officials have been holding continued talks since January over a possible peace process to bring an end to the 17-year-old war, the longest in US history.
During his State of the Union address, President Trump said that he planned to reduce the number of troops in Afghanistan as the US works toward a peace process. There are currently 14,000 US troops in the country.
In February, Acting Defense Secretary Patrick Shanahan said the US would not withdraw or reduce the number of troops without first consulting with NATO allies.