PANAMA CITY, Fla. (WMBB) — The U.S. Department of Justice has charged a former soldier with first-degree murder in a killing on an Army Base in Germany.

The murder went unsolved for more than 20 years but Thursday investigators said they now believe Shannon L. Wilkerson, 42, killed Amanda Gonzales, 19, on Nov. 3, 2001.

The slaying happened at Fliegerhorst Kaserne, then a U.S. Army base in Hanau, Germany, federal prosecutors from the Northern District of Florida wrote in a news release.

“Wilkerson was a member of the Armed Forces at the time of the alleged offense but was later discharged from the Army,” they added.

The FBI wrote that Gonzales was four months pregnant at the time of her murder. 

“Gonzales, on her first assignment in the Army, was assigned to the Headquarters Supply Company of the 127th Aviation Support battalion as a cook at the time of her death,” the FBI wrote. “The cause of death was ruled a homicide by asphyxiation.”

Federal prosecutors added that Wilkerson is charged under the Military Extraterritorial Jurisdiction Act, which gives the U.S. federal courts jurisdiction over crimes committed outside the United States by, among others, former members of the Armed Forces who are no longer subject to the Uniform Code of Military Justice.

Wilkerson is charged with one count of first-degree murder and faces a maximum penalty of life in prison. He is expected to be tried in Pensacola.