Davido and Karen Koep are now believed to be dead, authorities say.Photo:Thurston County Sheriff/Facebook

Washington Chiropractor and Her Husband Mysteriously Vanished Under ‘Suspicious’ CircumstancesÂ

Thurston County Sheriff/Facebook

Police have arrested and charged a man in connection withthe Washington couple who has been missing since Monday.

“Working with our local, state and federal partners, we have gathered evidence to identify a suspect in their disappearance,” the office wrote.

The suspect will be held at Thurston County Jail on one count of first-degree murder and one count of ​​first-degree kidnapping.

Police now believe that the missing persons — Karen Koep and her husband, identified only as Davido — are dead, per the statement.

“Throughout the investigation, we have been in contact with the family of the missing couple, and sadly, we do not believe the couple survived the attack at their residence,” the office wrote.

Police also noted in the statement that detectives “have worked tirelessly” in investigating the couple’s disappearance and that “additional information will be released when available.”

After Koep did not show up for work, police carried out a welfare check at the couple’s residence, and determined that both were missing, along with their car, a 2015 Toyota Yaris, per apostfrom the sheriff’s office.

Last week, Joe Blade, who owns a realty company at the same location as Koep’s practice, told PEOPLE he last saw the chiropractor around Wednesday the week before her disappearance was announced.

The following day, her office answering machine directed callers to a different clinic because it was closed “due to an emergency.”

Last week, Koep’s sister, Pauline D. Dutton, told PEOPLE that her family is in “complete shock,” and have no idea what might have happened. The couple was scheduled to visit her in Oregon during Thanksgiving week.

She also said that the chiropractor “is the strongest woman you’ll ever meet in your life.”

“She is probably selfless to a fault,” she told PEOPLE. “She doesn’t have the time to take care of herself sometimes because she’s always giving to others.”

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Dutton also spoke withNBC Newsfollowing her sister’s disappearance, telling the outlet that she does not think Koep nor Davido would leave their home without telling anyone.

“I know that they didn’t walk away from their house on their own, let’s put it that way," Dutton said.

“They didn’t just walk out of there. They’re not in Bora Bora having a vacation,” she added. “They are missing, and I don’t think they went willingly.”

source: people.com