On October 4, Johnson and three other US soldiers, Staff Sgts. Bryan Black, Jeremiah Johnson and Dustin Wright, were killed after engaging in a firefight with up to 50 Daesh-linked fighters, an incident widely described as an ambush.
"We can confirm that the Armed Forces Medical Examiner has positively identified these remains as those of Sgt. Johnson," Pentagon spokeswoman Dana White told CNN.
Johnson may have been held prisoner before being executed. The soldier's body apparently wasn't found until 48 hours after the attack, and was ultimately discovered a mile away from his fallen brothers-in-arms. Reports said his hands were bound, indicating he may have been wounded in the battle, taken captive and executed.
Johnsons's widow, Myeshia Johnson, said the government wouldn't let her see her fallen husband's body, and the lack of government transparency about the circumstances under which he died has only added to the family's suffering.
"It is unconscionable, it is painful to this family," Rep. Frederica Wilson (D-FL), who is close with the Johnsons, said Tuesday. "How much can a Gold Star family take when you say to them that you cannot have an open casket funeral but we don't know what happened to your husband, we don't know what happened to your son, we don't know what happened to your brother."
Johnson's family held a closed casket funeral for the deceased service member last month.
