Former UFC champion BJ Penn’s Octagon return has been delayed following criminal allegations against the fighter.

According to Delaware (Ohio) County Sheriff’s Office record, a woman reported being assaulted by Penn back in 2015 while both were in Hawaii. The report states that the matter has been given to the Hawaii police.

The UFC released a statement concerning the matter on Thursday:

“UFC is aware of the recent allegations made against BJ Penn. The organization requires all athletes who compete in the UFC to act in an ethical and responsible manner, as detailed in the UFC Fighter Conduct Policy. UFC will not tolerate violations of the policy. Every athlete is deserving of proper review and this situation, as with any serious allegation, will be investigated by an independent party and thoroughly reviewed by the UFC. The UFC organization will also cooperate with any law enforcement investigation. In light of the serious allegations, UFC has postponed plans to book Penn for an upcoming bout until more details are determined.

UFC holds athletes who compete in the organization to the highest standard and will continue to take appropriate action, if and when warranted. It is important to note that Penn is considered innocent until proven guilty and UFC is not prejudging this matter.”

Penn, 37 years old, has not fought since 2014, but returned to training in New Mexico instead of Hawaii recently.