ST. PETERSBURG, Fla. — A Minnesota woman who led authorities on a cross-country manhunt pleaded guilty Tuesday in a Florida courtroom to fatally shooting a woman who prosecutors said was targeted because the two looked alike.

Lois Riess, 57, singled out Pamela Hutchinson because they shared similar features, and Riess wanted to assume Hutchinson’s identity while on the lam, officials from the Lee County State Attorney’s Office said. She was sentenced to life in prison.

With a shock of white hair, Riess garnered national attention as the “fugitive grandma” before she was captured in April 2018 in Texas.

“It was certainly one of the more unusual cases in my 25 year career as a prosecutor,” said Rich Montecalvo, chief assistant state attorney.

Riess’ saga began in March 2018, when her husband, 54-year-old David Riess, was found dead at the couple’s Blooming Prairie, Minnesota, home. Lois Riess forged checks to steal $11,000 from her husband’s account, traveled south to Florida and landed in Fort Myers, prosecutors said.

Investigators said surveillance footage showed the two women near Hutchinson’s Fort Myers condo-hotel room on April 4 and April 5. For the next two days, Riess was recorded on surveillance video — at times carrying garbage bags to the parking lot — but Hutchinson wasn’t seen at all.

After killing Hutchinson, Riess made her way to Texas while using Hutchinson’s credit cards and vehicle, police said.

On April 19, 2018, Riess was drinking cocktails at a South Padre Island, Texas, waterfront restaurant when she was arrested by two federal deputy marshals. An employee recognized her from surveillance video broadcast on television.

On Tuesday, Riess pleaded guilty to first-degree murder with a firearm, grand theft of a motor vehicle, grand theft, and criminal use of personal identification information of a deceased individual. Prosecutors withdrew the possibility of the death penalty on the murder charge as part of the plea deal.

Samantha Syoen, the spokeswoman for the State Attorney’s Office, wrote in a news release that Hutchinson’s family was supportive of the plea agreement because they wanted Riess to be incarcerated for the rest of her days.

“This defendant will never get out of prison,” said State Attorney Amira Fox. “This life sentence also alleviates any appellate issues that could arise and guarantees she will never be free again. It also allows the family of the victim to not have to go through the details of this crime at a trial.”

Riess waived extradition Tuesday to face charges in Minnesota in connection with her husband’s slaying. Messages left with authorities in Minnesota were not immediately returned Tuesday.

Montecalvo said that if she stands trial and is convicted in Minnesota, corrections departments in both states will determine where she’s incarcerated.

“Frankly I don’t care,” he said. “We believe that justice is done for the victim’s family. They just wanted to make sure she was never ever released from prison.”

Her son, Braden Riess, said in 2018 that she was a “good lady,” but had her “own demons.”

“Something happened in her brain that made her snap,” he told “Inside Edition” in 2018.