A Vancouver teen who was found dead earlier this month is believed to have been strangled to death after her alleged killer learned she was transgender, court documents show.

Nikki Kuhnhausen, then 17, was reported missing on June 6. On Dec. 7, a hiker found her skull in the woods near Larch Mountain, and on Tuesday, police arrested David Bogdanov and charged the 25-year-old with her murder.

On Wednesday, Bogdanov appeared in Clark County Superior Court on a charge of second-degree murder and is being held without bail in the Clark County Jail.

Based on phone records, police believe that Bogdanov may have been seeking a sexual encounter that night, and upon finding out that Kuhnhausen was transgender, became enraged and strangled her to death, then drove her body out to Larch Mountain and left it there.

“I believe that David became enraged at the realization that he had engaged in sexual contact with a male whom he believed to be female and strangled Nikki to death,” Vancouver Police Officer Jason Mills wrote in the probable cause affidavit.

A probable cause affidavit released on Wednesday shows that Kuhnhausen and Bogdanov met up in the late hours of June 5 after communicating on the social media app Snapchat.

Kuhnhausen’s mother told police that her daughter had been staying at a friend’s house. That friend confirmed that Kuhnhausen left her house that night, then returned to the house before 5 a.m. on June 6, and then left with an “unknown ‘older’ Russian male” and didn’t come back.

According to court documents, Kuhnhausen didn’t have a cellphone but used her friend’s cellphone to access her Snapchat account with Bogdanov. After meeting up with him on the night of June 5, she came back to her friend’s house in the early morning and told her friends that Bogdanov was going to help her get a cellphone.

Police got a search warrant for Kuhnhausen’s and Bogdanov’s Snapchat accounts and confirmed that the two had been communicating and that he had picked her up on the morning of June 6.

In late June, police began trying to find Bogdanov, contacting two of his brothers in Vancouver, court documents show. Both brothers said they didn’t know about their brother’s encounter with Kuhnhausen. One of the brothers gave police an updated phone number for Bogdanov, but he did not answer their calls.

Bogdanov responded to police in September, several months after they had begun trying to reach him. In October, Bogdanov met Vancouver police for an interview. He said he remembered meeting Kuhnhausen on the night of June 5. He said he saw her Main Street in Vancouver and invited her to join him and his brothers at a bar, court documents show.

Bogdanov said the two exchanged addresses, and that later that night, he picked her up in a van and agreed to take her to a friend’s house so she could get her cellphone. He said that while they were in the van outside his brother’s house, they were “chit-chatting,” and Kuhnhausen told him that she was assigned male at birth. Bogdanov told police that he had been shocked and uncomfortable to learn that Kuhnhausen was transgender and asked her to get out of the van and leave. He told police that homosexuality is unacceptable in Russian culture and denied having any sexual contact or discussion of it with Kuhnhausen. He told police that Kuhnhausen walked away from the van, and he never saw her after that. He told police that he went straight to work after the encounter.

But according to Bogdanov’s cellphone records on June 6, around 4:30 a.m., a few hours after he was in Vancouver near his brother’s house, his phone was pinged in the area of Larch Mountain — in the area where Kuhnhausen’s skull was eventually found.

According to phone records, he also called an adult video store and several female escort ads that night, indicating that he was looking for a sexual encounter with a woman. Bogdanov did not mention this to police in his interview.

On Dec. 7, a hiker found a skull near Larch Mountain in a steep, densely wooded embankment area. Search and rescue crews responded and found other human remains and items like jewelry and clothing, which were associated with Kuhnhausen.

One of the items investigators found was a set of hair extensions they believe belonged to Kuhnhausen. Attached to the hair was what police believed to be a ligature, and the hair was tied up in the knot of the ligature. They also found a hyoid bone tangled up in the hair. The medical examiner determined Kuhnhausen had died after being strangled by the ligature.

Bogdanov’s next court date is scheduled for Jan. 2.

—Jayati Ramakrishnan; 503-221-4320; jramakrishnan@oregonian.com; @JRamakrishnanOR

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