One student was taken to the hospital following a mishap in a biology lab at Lakeland High School Monday morning.

A student combined ammonia and bleach, which created the gas vapor chloramine, according to a news release from the city.

All 23 students were immediately removed from the classroom, and the windows were opened to allow the vapors to dissipate, according to the release. A fan was also placed in the classroom to help push the gas out of the room.

Five students and one teacher’s assistant complained of exposure, according to the release. The students were being treated by the school nurse upon arrival of Suffolk Fire and Rescue units.

One student was taken to Sentara Obici Hospital complaining of lightheadedness and headache, the release stated. Suffolk Public Schools spokeswoman Bethanne Bradshaw said the male student was “doing fine” when administrators left the hospital.

The teacher’s assistant was treated at the scene by rescue workers. Parents of affected students were notified by phone, and a letter was sent home with all students in the class at the end of the day.

All students who had been in the room were checked on later in the day, according to the letter from Principal Thomas Whitley. Students were told that if any symptoms developed, they should report directly to the school nurse.

Bradshaw wrote in an email that administrators were “investigating the incident to determine whether it was intentional or accidental.”

The classroom remained closed for the rest of the day, according to the city release. Suffolk Fire and Rescue personnel contacted state hazardous materials officials, who endorsed all actions taken.

Rescue units were on the scene for nearly two hours after receiving the call at 9:54 a.m. Three engines, one ladder truck, a rescue truck, two medic units and the battalion chief responded to the incident.