A Riverton High School student accused of involvement in an attack on a younger student during a wrestling trip earlier this year told a Casper judge on Friday that he intends to plead guilty to at least one criminal charge filed in connection with the case.

Hayden Wempen, 18, is charged with two misdemeanor counts of unlawful contact stemming from what an investigator described as "a series of assaults" that took place on a school bus which was traveling within Natrona County on the evening of January 4.

Wempen's attorney, Jeffrey Stanbury, told Natrona County Circuit Court Judge Steven Brown on Friday that a plea agreement is in place with the Natrona County District Attorney's office, but has not yet been filed with the court. As such, Wempen did not enter pleas during Friday's court hearing.

Brown set Wempen's bond at $1,000 personal recognizance and said a change-of-plea hearing will be set for a later date. Each of the charges carries a maximum penalty of six months behind bars and a fine of $750.

Stanbury was not immediately available to detail the plea agreement, and the Natrona County District Attorney's office said only that charges have been filed and the case is moving forward.

According to an affidavit filed in the case, "Students described the assaults as when upperclassmen wrestlers grabbed ahold (sic) of underclassmen wrestlers, physically held them down or placed the underclassmen in a choke hold, covered the underclassmen's mouth to prevent them from yelling, and then forced their finger(s) into the underclassmen's anus area by pushing clothing in or near the underclassmen's anus."

On the evening of Jan. 4, the Riverton High School Wrestling team was on their way to a tournament in Douglas.

Video surveillance cameras captured nine assaults which took place over the course of 24 minutes. Wempen was identified as one of three wrestlers who grabbed the victim, dragged him to the back of the school bus, held him and forced their hands into the area of the victim's private parts.

Another teen charged in connection with the incident, Peyton Rees, allegedly admitted that he held a student down on eight occasions that night.

Rees also faces two misdemeanor counts of unlawful contact. According to a criminal summons filed July 3, Rees was due to appear in court at the same time as Wempen on Friday morning. However, Rees did not appear, and Judge Brown did not ask whether Rees was present in the courtroom.

Rees's attorney, Vance Countryman, did not immediately return a message seeking clarification on the court date.

Three wrestlers from the Riverton High School team were expelled for assaulting and sexually harassing eight teammates during the Jan. 4 incident. The expulsions were for one year.

Fremont County School District No. 25 Superintendent Terry Snyder says the actions were "appalling" and the perpetrators "needed to be held accountable."

Wempen won a state championship in February 2017. Rees received a good sportsmanship award from the Wyoming High School Activities Association in September 2017.