The immense joy of Spencer and Monique Tepe was unmistakable on their wedding day in a 2021 video shared by the family, which captured them exchanging vows. The then newlyweds embraced and laughed in their Columbus, Ohio, home as friends and loved ones cheered them.

But just one month before their fifth anniversary, the same setting where the couple began their life together became the site of unspeakable tragedy. The respected dentist, 37, and his 39-year-old wife, a stay-at-home mother, were found dead on Tuesday after being gunned down in their upscale home while their two young children were inside.

A memorial of roses and sunflowers now grows outside the home as news of the shocking killings spread nationwide just days after Christmas, generating more questions than answers.

Law enforcement has been reluctant to disclose any details about a possible suspect or motive but said the killer or killers of the young couple remain on the loose. Even more mysterious, police revealed there were no obvious signs of forced entry, and no firearm was found at the scene, CNN affiliate WSYX reported.

Police are asking the public for any information on a case they say is being investigated as a double homicide, not a murder-suicide.

Here’s what we know and don’t know about the tragedy:

How concerned friends and colleagues led police to home

Spencer Tepe had rarely missed work at Athens Dental Depot, located about 75 miles southeast of the family’s Columbus home, and he and his wife were always responsive, according to the owner of his practice, Dr. Mark Valrose, CNN affiliate WSYX reported.

But on Tuesday morning, he didn’t show up for work, spurring concern from his colleagues that continued to grow when they could not get in touch with him or his wife, according to 911 calls reported by WSYX.

Valrose made the first 911 call at around 8:58 a.m. and asked police to conduct a wellness check, telling the dispatcher: “He is always on time, and he would contact us if there were any issues,” according to the recording.

“I don’t know how else to say this, but we are very, very concerned. This is very out of character for him,” he continued. “We can’t get in touch with his wife, which is probably the more concerning thing.”

At 9:22 a.m., an officer arrived at the home to perform the welfare check, but no one answered the door, WSYX reported, citing police records.

Around 30 minutes later, Tepe’s colleagues and a friend arrived at the home, but also did not get a response, the dispatch records showed. A man at the scene also called 911 at 9:56 a.m., saying he heard children crying inside.

“I can hear kids inside, and I swear I think I heard one yell,” the caller said, according to dispatch audio. “But we can’t get in. At this point, I don’t know if I need to break the door in to get in the house or what.”

Two minutes later, another colleague of Tepe called 911 to say they had been unable to reach him for about three hours, according to the recordings obtained by WSYX.

Around 10:03 a.m., a friend of Tepe, who said the two last spoke the day before, was audibly distressed as he called 911: “There’s a body,” he reported.

“Our friend wasn’t answering his phone … we just came here and he appears dead,” the friend said.

Officers found the bodies of Spencer Tepe and Monique Tepe in their home in the Weinland Park neighborhood, Columbus police said.

Their two children, ages 1 and 4, were also found unharmed in the residence, police said.

How police will investigate the case

Columbus police have not issued any warnings to the community about an ongoing threat, and the agency did not respond to CNN’s questions about the timing of the killings, whether the Tepes were specifically targeted or any information about a suspect or motive.

The Franklin County Coroner’s Office told CNN autopsy reports can take between eight and 10 weeks to complete. A police incident report from Tuesday said Spencer and Monique Tepe were victims of homicide.

There is a police crime camera situated on a utility pole at an intersection located a few hundred feet from the Tepes’ home, according to The Columbus Dispatch. CNN has asked police whether any neighborhood cameras captured any relevant clues about what took place.

To help zero in on a motive and possible suspects, investigators will examine forensics, the possible entry of the killer, whether anything was stolen from the home and the Tepe family’s background to determine any further threat to the rest of the community, according to CNN Senior National Security Analyst Juliette Kayyem.

Without any recovered firearm, it’s not surprising detectives would investigate the deaths as a double homicide and not a murder-suicide, Kayyem said. “The other clue is, of course, the children are left safe.”

Either of two scenarios for how the crime unfolded seems to be most likely, Kayyem said: A “stranger at the door who just happens to kill this couple, or some narrative that might explain why they were targeted.”

This type of crime is “exceptionally rare” given there were no signs of forced entry, she continued. “… You’re going to look at people who they may have known or people who knew where they lived, unfortunately, and begin there.”

“Maybe this was random. But the … national data suggests both how uncommon this is as well as the likelihood that there may be someone who knew them who was involved with this,” Kayyem said.

What we know about the ‘deeply happy’ couple

Spencer and Monique Tepe “shared a beautiful, strong and deeply happy relationship,” bonded by a love of travel, laughter and a mission to “build a life rooted in love,” said their family.

“We are heartbroken beyond words,” reads the statement on behalf of the Tepe family.

As the devastating loss of the couple permeates their community, the family said they are “committed to seeing this tragedy fully and fairly brought to justice” and to honoring them by protecting the future of their beloved children, who are now in the care of relatives.

Meanwhile, Spencer Tepe’s employer, Athens Dental Depot, announced its closure for the rest of the week as they shared news of the “sudden passing” of the couple on Facebook.

“He will be deeply missed by our team and the many patients he cared for over the years. Our thoughts and sincerest condolences are with their families and loved ones during this very difficult time.”

Spencer Tepe, a graduate of Ohio State University and a member of the American Dental Association, was a “devoted and proud father, a loving partner, and a friend to everyone he met,” his family said.

He was fluent in Spanish, a major fan of the Bengals and Buckeyes football teams and had a generous and energetic spirit, they said.

His wife Monique Tepe had a background in childhood education and “brought care and intention into everything she did,” their family said. She was described as a loving, patient and joyful mother “whose warmth defined her.”

The couple, their family said, were “extraordinary people whose lives were filled with love, joy, and a deep connection to others.”

CNN’s Holly Yan, Caroll Alvarado and Yan Kaner contributed to this report.

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