With her platinum-blond hair and cherubic smile, Lois Riess looks in photos like what she is — a 56-year-old grandmother from small-town America.

And that, authorities say, makes her even more dangerous.

For the past three weeks, police say, Riess has led them on a nationwide pursuit — from the Minnesota worm farm where they found her husband shot to death last month; to Florida, where they think Riess befriended and killed a woman who looks like her to steal her identity; and finally to Texas, where police fear Riess may find her next target.

“She smiles and looks like anyone’s mother or grandmother,” Carmine Marceno, a deputy sheriff in Lee County, Fla., told NBC News after the authorities lost Riess’s trail. “And yet she is calculated, she’s targeted, and she’s an absolute coldblooded killer.”

Federal, state and local law enforcement officials continued a multistate search Tuesday for Riess, who authorities said should be considered armed and dangerous.

Deputy U.S. Marshal John Kinsey said marshals have received about two dozen tips, many in southern Texas, and are following up on them one by one.

“We’re working tips now, still trying to track her down,” Kinsey told The Washington Post.

He added: “Hopefully, she turns up one way or another.”

The Lee County Sheriff’s Office released footage from April 5 showing Lois Riess, 56, who is suspected of two murders. (Lee County Sheriff's Office)

Riess and her husband, David Riess, were well-known and liked by the 2,000 or so other residents of Blooming Prairie, Minn., according to the Minneapolis Star Tribune. The couple were regulars for lunch at the local Servicemen’s Club, nearly 100 miles south of Minneapolis. David Riess owned and operated a farm for fishing bait — Prairie Wax Worms.

Concerned that David Riess had not been seen in more than a week, the Star Tribune reported, one of his business partners asked police to look for him.

Officers found him dead of gunshot wounds at the worm farm March 23, the sheriff of Dodge County told the newspaper. It was unclear how long he’d been dead.

Lois Riess had left town by then. According to the Star Tribune, police suspect that she forged her dead husband’s signature before his body was found, transferred nearly $10,000 into her account and headed to a casino across the Iowa border.

“Dubbed by local authorities as ‘Losing Streak Lois,’ she is known to have a gambling addiction and often frequents casinos,” the U.S. Marshals Service said.

She had left Iowa by the time police tracked her there in late March, the Star Tribune wrote. State officials began to paste her photos on Facebook, urging anyone who saw her to call 911 and not go near her.

From Iowa, police say, Riess drove to Lee County. There, they said, she met a woman named Pamela Hutchinson, 59, with a similar shade of light-blond hair.

“She befriended this woman. The woman probably gave her some sob story,” Hutchinson’s cousin Daniele Jeffreys later told WTVR. “My cousin went out helping the world. … She’s just giving to a fault. To her death.”

On April 5, the two women were recorded on a surveillance camera at the Smokin Oyster Brewery in Fort Myers, Fla., sharing a laugh.

According to the Star Tribune, another surveillance camera photographed Riess at Hutchinson’s condo in the same city.

On April 9, police found Hutchinson shot to death at her condo. Hutchinson’s uncle told WTVR she’d been shot through the heart.

The dead woman’s purse had been emptied, sheriff’s investigators said. Her identification, credit cards and car keys were gone. So was her car.

The Minnesota woman being sought in connection with her husband’s murder last month is now a suspect in a second murder…

Posted by Minnesota Bureau of Criminal Apprehension on Friday, April 13, 2018

The search for Riess was made a multistate and federal matter, with the FBI and Marshals Service helping in the hunt, according to authorities. More public advisories went out, with more photos of Riess and the car she was believed to be traveling in, which was the car of the woman that police said she killed.

The vehicle was spotted near Corpus Christi, Tex., this month, Florida authorities said at a news conference.

Lt. Chris Hooper, a spokesman for the Corpus Christi Police Department, told The Post that federal authorities said the vehicle had been seen within 60 miles of Corpus Christi; local authorities, however, have no evidence that the car has been seen within the city limits.

“We are definitely aware of the possibility of the offender being in this area,” he said.

However, Riess’s current whereabouts are unknown.

The obituary for David Riess was published last week and mentioned his children and grandchildren but not his wife.

“Pure evil,” Hutchinson’s cousin told WTVR. “That’s really the only thing that could resonate with my system. … It’s just evil that flowed through.”

In Florida, the deputy sheriff told NBC he had never seen a killing like it.

“This is the first time in my career I’ve seen someone steal someone’s identity and target them for the way they look in order to murder them,” Marceno said.

And he worries that it won’t be the last.

“I suspect Riess at some point in time will have no resources, and she will become more desperate,” Marceno said, “and may kill again.”

This story, which was published April 16, has been updated.

Read more: