A federal grand jury in Madison, Wis., returned the indictment charging Kristen Smith with kidnapping, which carries a maximum sentence of life in prison, U.S. Attorney John Vaudreuil announced.
The indictment had been expected after the FBI filed a criminal complaint accusing Smith in the Feb. 6 kidnapping of newborn Kayden Powell. Smith, 31, of Aurora, Colo., has been jailed in Iowa since her arrest, which came hours after the baby went missing.
Federal law enforcement officials will transfer Smith to Wisconsin before an initial court appearance scheduled Friday afternoon at the federal courthouse in Madison, said Myra Longfield, a spokeswoman for Vaudreuil.
Investigators say Smith took the baby from a Town of Beloit, Wis., home where her half sister, 18-year-old Brianna Marshall, was staying after giving birth on Feb. 1. Marshall woke up to find her newborn and Smith gone in the middle of the night, and called 911.
Police contacted Smith on her cellphone as she was driving through Iowa and directed her to pull over at the nearest gas station for questioning. An officer in West Branch, Iowa, found baby clothes, a stroller and a car seat in Smith's vehicle - but no sign of Kayden. Smith denied any knowledge of his whereabouts, but was taken into custody on an outstanding warrant from Texas.
Police searched through Iowa, Illinois and Wisconsin for the newborn. Authorities say the police chief in West Branch, Iowa, found him 29 hours later behind a gas station about 500 yards from where Smith was arrested. He was wrapped in blankets inside a plastic storage bin.
Despite temperatures that went well below zero, Kayden was alive and healthy. His survival stunned some medical professionals, who said they did not believe a baby could last that long in the weather.
Asked whether any others were suspected of involvement, Longfield said that "the investigation is ongoing" and didn't elaborate.
The FBI complaint says investigators found email and Facebook messages in which Smith falsely claimed to have been pregnant or given birth, as well as a prosthetic pregnancy belly in her car.
Wednesday's indictment adds no new details, saying only that Smith "knowingly and unlawfully seized, confined, kidnapped, abducted and carried away the victim, K.P., and willfully transported the victim in interstate commerce from Wisconsin to Iowa." The indictment notes that Smith also goes by the name of Kristen Pearson.
The indictment is by far the most serious criminal charge against Smith. But records show she has also faced several other fraud and theft charges, including in Wisconsin, Indiana and Texas. And a county prosecutor in Iowa charged her last week with child endangerment for allegedly leaving Kayden in the cold.
Smith has been held at the Cedar County Jail in Tipton, Iowa, and has not responded to a written interview request. In a statement authorized by Smith last week, defense attorney Victoria Noel said that Smith wanted to express concern for her sister's well-being after the family's hardship but did not take responsibility for causing it.
"She understands her sister has gone through an ordeal and is hoping she's doing all right, regardless of what may or may not have happened," Noel told reporters.
Once in Wisconsin, U.S. Marshal Dallas Neville said Smith would be housed in a county jail that he would not identify for security reasons.