NORMAN, OK. (CNN) — Four Norman, Oklahoma, high school wrestlers have been charged with felony rape for allegedly assaulting a 16-year-old and a 12-year-old, according to court documents CNN obtained Tuesday.

Tanner Shane Shipman, 18, and three minors — two who are 17 and one who is 16 — are charged with raping the two victims on a school bus on January 9 while their Norman North High School wrestling team was returning home from a tournament in Pauls Valley. The district attorney viewed audio and video from the bus before charging the students.

Sam Talley, an attorney for Shipman, told CNN his client has pleaded not guilty. Talley said he and other attorneys will get a chance to view the video on Wednesday and won’t comment on the case until then.

Shipman was released after paying bail of $5,000.

Elton Jenkins, an attorney for one of the minors, said the other three defendants also bonded out.

“We’re fighting this,” he said.

Court documents say that soon after the bus left, Shipman helped the others restrain a 16-year-old wrestler under the seats at the back of the bus. Two of the accused allegedly inserted their fingers into the victim’s anus over his clothing.

Shipman forced the teen victim’s hand onto his crotch and shouted, “Touch my balls!” the documents say, and then Shipman and the three others tried to “lure” a 12-year-old male wrestler to the back of the bus. Shipman allegedly grabbed the victim and dragged him to the back of the bus.

Soon afterward, the bus driver activated the interior lights and escorted the victim back to his seat, the documents say. Once the lights were turned back off, the alleged victim was persuaded to come to the back of the bus.

One accused teen allegedly then restrained the victim, while another put a condom over the fingers of one hand and inserted his fingers into the 12-year-old’s anus, over his clothing, the documents say.

When the bus arrived at Norman North High, the 12-year-old victim was assaulted a second time, the indictment says, as Shipman and the others forced the boy to a secluded area around the corner of the school building. The 12-year-old was restrained while Shipman and another accused teen again inserted fingers into the 12-year-old’s anus, the court documents say.

The boy escaped, but Shipman and the others chased after him, the documents say, and Shipman tackled the young victim, forcing the boy between two parked cars.

The alleged assault ended when the victim’s parent arrived at the parking lot.

School district statements

Dr. Joseph Siano, superintendent of Norman Public Schools, first issued a statement saying officials followed procedures that allowed them to investigate and take swift action. “We appreciate the individuals who came forward to provide information, the Norman Police Department’s thorough investigation and the quick action by the district attorney on this incident. We are well-prepared to handle situations like this and have programs in place to support students who experience trauma,” the statement read.

“And, while we believe the district’s policies regarding student supervision are strong, we continuously evaluate our procedures to ensure they are followed. As we address the inappropriate behavior displayed by several students, we remain committed to supporting the vast majority of our student athletes, who are quality individuals that demonstrate positive behavior and strong character traits.”

Later Tuesday, Siano released a second statement saying the four charged students are suspended and two coaches have been dismissed.

Siano said officials have worked to strengthen travel procedures and now require increased supervision on all student trips so that supervisors will be able to see students at all times. “Our hearts break for these victims,” it read, “and our student advocacy coordinators are working closely with them through this traumatic time.”

Shipman will return to court for a discovery hearing on February 26 at 10 a.m., according to online court records.

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