Patrick Frazee’s attorneys filed a list of defenses and witnesses Tuesday afternoon, saying there could be evidence presented at his murder trial next month that other people were involved in the killing of Kelsey Berreth.

The deadline for filing alternate suspects to the court was Monday, but Frazee’s defense team had not filed those documents by then, Robert McCallum, spokesman for the Colorado Judicial Branch, confirmed. It’s unclear whether a Teller County District Court judge will accept the documents filed Tuesday.

In Tuesday’s filing, defense attorneys allege that Krystal Lee, also known as Krystal Jean Lee Kenney, may have been involved in the murder as part of their defense of Frazee. Kenney, an Idaho nurse who had an affair with Frazee, pleaded guilty in February to tampering with evidence in the case and told police Frazee, 33, admitted to beating his fiancée Kelsey Berreth to death and burning her body.

The filing said as part of Frazee’s denial of the crimes he’s accused of, “it is anticipated that as part and parcel to general denial, there may be evidence that other individuals committed or fabricated portions of the crimes alleged against Mr. Frazee, to include Krystal Lee.”

Frazee, of Florissant, is accused of killing Berreth, 29, on Thanksgiving Day, though he denies the allegations. The two have a daughter who is in the custody of her grandparents. Frazee alleges that Berreth abused the 1-year-old girl.

Berreth was last seen near her home near Woodland Park and investigators have not found her body.

A jury trial is scheduled to begin Oct. 28. Frazee is next set to appear in court Oct. 18.