"I want to apologize to Rebel nation, my teammates and coaches for my actions last weekend," Nkemdiche said in statement released by the school. "I made a mistake and put myself in an environment that doesn't reflect who I am as a person."
After arriving at the Grand Hyatt Atlanta in Buckhead, police searched the room Nkemdiche fell from on Saturday night. According to the incident report, the investigating officer discovered "seven rolled marijuana cigarettes, rolled in Cigarillo Blunt papers" and reported that "the room was in complete disarray."
Officers linked the drugs to Nkemdiche, who was charged with possession of marijuana.
According to the incident report that was released Monday, Nkemdiche went through his hotel room window and fell onto a ledge that encircles the building. He then fell from that ledge to the ground.
Police estimated Sunday that both falls were about 15 feet. Police also reported to ESPN.com on Sunday that the hotel room window was broken. The investigation into how Nkemdiche fell is ongoing, according to the Atlanta PD.
Nkemdiche refuted a FOX Sports report that cited sources who said he used synthetic marijuana on the night of his fall.
"Contrary to a report by FOX Sports, I did not use synthetic drugs," Nkemdiche said. "I realize the dangers of drugs and alcohol and regret the lapse in judgment. This does not reflect the core values that my mother and father instilled in our family. I am a very spiritual person, and drugs have no place in my belief system."
Synthetic marijuana does not show up on drug tests.
According to the incident report, Nkemdiche was conscious and breathing while lying on the ground near the Hyatt's sidewalk and driveway. Atlanta Police spoke to Nkemdiche and a group of several associates, and none of them said they knew why Nkemdiche had fallen out the double-pane window.
Nkemdiche later met with police investigators at Grady Memorial Hospital, where he had been transported in stable condition after the incident.
Ole Miss coach Hugh Freeze said Monday that he was told by Nkemdiche that he had gotten stitches in his back and leg and also had a swollen ankle.
"I said, 'Are you OK?' and he said, 'Yes, I am OK, Coach,'" Freeze said. "He said he was sorry. I said, 'We will talk about all the details after we talk about all the facts, but I'm glad that you are OK.'
"Sometimes, when bad things happen, there are some silver linings. It's a blessing that he wasn't on the 10th floor; it could have been tragic. That was the short conversation."
Freeze said he wasn't sure whether Nkemdiche would be back in time for the Sugar Bowl.
Nkemdiche was ESPN's No. 1 overall prospect when he signed with Ole Miss out of Grayson High School, which is located in Loganville, Georgia, just outside Atlanta.
He is considered one of the top prospects for the 2016 NFL draft should he decide to forgo his senior season with the Rebels. ESPN's Mel Kiper Jr. lists Nkemdiche as the No. 5 overall prospect on his Big Board and the top defensive tackle.
"As I move forward, I have learned a valuable lesson about the ramifications of a bad decision," Nkemdiche said. "I have worked very hard to have this platform, and I want to use it in the right way and be a role model for young players. I am sorry for putting Coach Freeze in this position and I will accept whatever consequences are necessary, but my hope is to finish this year's journey with my brothers."
ESPN.com's David Ching and The Associated Press contributed to this report.