THURSTON COUNTY, WASHINGTON: In a shocking turn of events, the Thurston County Sheriff's Office announced that a suspect had been taken into custody in connection to the disappearance of a Washington couple who are believed to be dead.

Karen Koep and her husband Davido had been missing since Monday, November 13, according to authorities, reported NBC News.

Who is the suspect behind Karen Koep and Davido's murder?

The sheriff's office stated that they had identified a suspect on Friday night, November 17, and disclosed that they do not believe the missing couple was alive.

The suspect who was known to the victims has been identified as a man from Olympia, Washington, who is in his 40s.

The man who lives east of Lacey, where the couple lived was taken into custody on one count of kidnapping and two counts of first-degree murder.

Who were Karen Koep and Davido?

On Monday, Koep and her partner, Davido were reported missing when Koep failed to show up for her work as a chiropractor. According to the sheriff's office, concerns escalated when neither Davido nor Koep could be reached, leading to a police investigation.

Koep's sister, Pauline Dutton stated that authorities conducted a wellness check on their home in Lacey but found no signs of the couple's presence.

Initially, the sheriff's office stated that Koep and Davido vanished under “suspicious" circumstances. However, authorities did not disclose additional details about the investigation.

The missing couple's car, a 2015 silver Toyota Yaris, was found abandoned on a street in Lacey. The vehicle was found at an intersection that is five miles away from Koep's workplace, according to her practice profiles on Google and ZocDoc.

On Thursday, November 16, Dutton expressed her skepticism about the missing couple leaving their home willingly and noted that the last conversation she had with Koepen was via text message on November 10.

Speaking to People, Dutton said, "My sister is the strongest woman you’ll ever meet in your life."

"She is probably selfless to a fault — she doesn't have the time to take care of herself sometimes because she’s always giving to others," she added.

Dutton added that their family is in "complete shock" following the death of Koep and Davido. They are also not aware of what led to tragic events at the victims' home.

The couple wanted to follow the family tradition of spending Thanksgiving week with their family before their tragic death, according to People.