The Colorado father accused of killing the mother of his child has pleaded not guilty to murder.

KOAA reports that Patrick Frazee, arrested for the murder of Kelsey Berreth earlier this year, pleaded not guilty in Teller County Court on Friday morning, in a hearing that was delayed several weeks after his attorneys waited for the results of unspecified tests, presumably related to evidence in the case.

Frazee will reportedly head to trial in October of this year.

Berreth, 32, went missing on Thanksgiving Day, and authorities have since said they believe she was killed in her Woodland Park home that day. Her remains have not been found, despite an extensive search of a Colorado landfill. A former girlfriend of Frazee’s, Krystal Lee Kenney, pleaded guilty to one count of tampering with evidence, and reportedly told investigators that she helped clean up the crime scene and dispose of evidence — following multiple requests from Frazee that she kill Berreth herself.

A motive for the crime is not yet known. The couple share a one-year-old daughter, and were at one point engaged to be married, though they did not live together.

Prosecutors are expected to hold a press conference on Friday with more details about the case.