Glenn Hartong / Cincinnati Enquirer via AP Parents and other family members cross under a police line to check on their children, on April 29, at LaSalle High School in Cincinnati, where a high school student pulled out a gun and shot himself in a classroom on Monday.

An Ohio student was in critical condition after shooting himself in an apparent suicide attempt that took place during a class Monday at an all-male Catholic high school in Cincinnati, police said.

The student, whose name has not been released at the request of the parents, pulled out a semi-automatic handgun shortly after 9 a.m. on Monday during an honors-level leadership class at La Salle High School, according to authorities.

Then, in the same room as 22 other students, he tried to end his life, police said.

The school was immediately placed on lock down and no other students were injured.

The youth was taken to a nearby hospital where the student is "fighting for his life," Greg Tankersley, La Salle's director of community development, told reporters.

Tankersley said the teen is an honors student who has completed more than 80 hours of community service and is working to become an Eagle Scout.

Following the incident, the family released a statement: “We thank all of you for your thoughts and prayers. We ask that the media please respect our privacy at this time so we can do what we need to do for our son and our family. We also ask that friends of our son and family please refrain from Facebook and Twitter comments. We appreciate the heroic efforts of UC Medical Center staff as they care for our son.”

Authorities have thus far not commented on how the student brought the gun into a classroom. Late Monday police swept the school with K-9 units as a precaution.

Distressed 911 calls from students reveal the chaos and panic that ensued following the single gun shot. Many in the room were unaware at the time that it was a suicide attempt and thought it could be an active shooter.

"We're at La Salle High School and there is a guy with a gun," one student frantically told the Hamilton County 911 dispatcher.

Groups of students huddled together throughout the high school as authorities arrived.

School officials praised Green Township Police and the Hamilton County Sheriff's Office for quickly responding and securing the scene. After the scene was deemed secure, students who had gathered in the gym were allowed to leave with parents. Counselors were also on hand to speak with the kids.

Classes will resume Tuesday with an all-school prayer service at LaSalle, officials said.

"We think it's important to have our young men back in the building so we can talk about it with them and help them deal with this situation," said Tankersley.