SAN DIEGO (KSWB/KUSI) — Four members of a fraternity at San Diego State University are facing criminal charges after one of the young men sustained third-degree burns on his body during a "skit" performed at their party, the county district attorney announced Monday. The incident, involving Phi Kappa Psi members, occurred last February, when the fraternity was on probation with the university over issues of hazing and conduct that threatens the health and safety of students. Prosecutors say three of the students — Lucas Cowling, Christopher Serrano and Lars Larsen — had "pre-planned" the skit for a party hosted at the fraternity house. The act involved Serrano setting Larsen on fire, according to the district attorney. Both were pledges at the time. Thousands flee as wildfires burn in and around Los Angeles Larsen sustained third-degree burns to roughly 16% of his body when the skit was performed, largely concentrated along his legs. The 19-year-old spent weeks in the hospital to receive treatment for the injuries, prosecutors say. Larsen and the other two involved in the skit, both of whom were 20 years old, reportedly had consumed alcohol prior to the stunt. After the incident, the district attorney alleges there was a coordinated effort by the three — as well as the chapter's president, 22-year-old Caden Cooper — to impede investigators' efforts, including deleting evidence and directing fraternity members not to speak to law enforcement. The fraternity members charged in the incident were between the ages of 19 and 22, according to the district attorney. (KSWB) In a statement shared with Nexstar's KSWB on Tuesday, a spokesperson for SDSU said the university was tipped off to the incident by an anonymous call, prompting the launch of an investigation by the SDSU police department. The findings from that investigation were then handed over to the district attorney. The fraternity was also placed on interim suspension by the school's Dean of Students Office, the spokesperson added. What kind of masks protect from wildfire smoke? All four students are each facing at least one felony charge in relation to the incident and purported cover-up, including recklessly causing a fire with great bodily injury, conspiracy to commit an act injurious to the public and violating the social host ordinance. Each pleaded not guilty and were released on their own recognizance. They were also barred from hosting or attending any fraternity parties or events. Additional hearings in the case are scheduled for early spring. SDSU declined to comment further on the specific case, but a spokesperson said the university "prioritizes the health and safety of our campus community and has high expectations for how all members of the university community, including students, behave in the interest of individual and community safety and wellbeing."