By Kate Raddatz

BLOOMING PRAIRIE, Minn. (WCCO) — A Minnesota woman is sharing new details about a grandmother who police say went on a killing spree.

Tess Koster says she saw Lois Riess just days before she allegedly killed her second victim. Riess went missing March 23 after allegedly shooting and killing her husband in Blooming Prairie.

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Investigators say she used the same gun to kill 59-year-old Pamela Hutchinson in Florida to steal her identity.

Just Thursday night, law enforcement arrested Riess in South Padre Island, Texas. That’s only 30 miles from the Mexican border.

WCCO’s Kate Raddatz shares how one Minnesota couple reported seeing Riess in Florida before she found her second victim.

“She came to Fort Meyers Beach because of us,” Tess Koster said.

Tess Koster, originally from Blooming Prairie, knew the Riess family for more than a decade.

“Have known them for years and years, they actually came and stayed at our cabin,” Koster said.

She and her husband winter in Fort Myers Beach, Fla., where they have rental properties. They had invited The Riess’ down to stay with them before.

On April 2, Tess noticed a white Cadillac Escalade outside her Florida home.

“Gal gets out, she has platinum almost white hair in a ponytail,” Koster said.

Tess says the woman was looking around at the rental properties. She asked if she needed any help

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“Our eyes met and I just oh my goodness my heart skipped a beat. It was Lois,” Koster said.

Tess knew Lois was missing after her husband was shot and killed at their Blooming Prairie home in March.

“She shook her head and said ‘Wrong house! Wrong house,” Koster said.

Lois Riess took off in her SUV. Tess ran back inside and told her husband to call 911.

A week later, the body of Pamela Hutchinson was found dead in a resort one block away from the Koster’s properties.

“I was just in shock. The sheriff’s department was so worried about us they came over and said you guys have to be careful,” Koster said.

Tess says she is sharing her story now because she was afraid for her safety while Lois was still at large.

The Minnesota grandmother was arrested shortly after a surveillance picture was taken of her at a Texas bar Thursday night.

“Just shocked. Had no idea. Both Lois and Dave are the sweetest people. Or were. I don’t know what happened,” Koster said.

Tess says that her daughter also got a phone call in Minnesota on the morning of April 2 from a woman, asking for the Koster’s address in Florida. She said she was a friend, but did not use her name.

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We reached out to the Lee’s County Sheriff’s Office, but did not hear back.

Kate Raddatz