NORTH PARK — Five students were injured during a cooking class accident involving hot chocolate at Northside College Prep Wednesday morning, authorities said.
The incident happened about 10:35 a.m. inside the North Park neighborhood school, 5501 N. Kedzie Ave., police said.
Students were in a cooking class and heating up hot chocolate when gas ignited, Chicago Fire Department spokesman Larry Langford said.
Approximately 40 minutes after the incident, the school received permission from the fire department to let students back into the building, according to a letter sent to parents by Principal Kelly Mest.
"We resumed our class schedule at that point and continued our school day as normal," she wrote.
One student was in serious condition after suffering facial and arm burns, Langford said. There were also concerns that the burns affected his breathing. He was taken to Illinois Masonic Medical Center.
Two others were hospitalized in fair-to-serious but stable condition, Langford said, and a fourth student was in good condition. A fifth student refused treatment.
"Our thoughts go out to these students and their families for a quick recovery," Mest wrote about the four hospitalized.
The accident happened inside a chemistry lab that doubled as a cooking space during a "colloquium" course. Cooking is one of several "colloquium" courses — seminars like sewing or bee-keeping outside the standard curriculum — students take each Wednesday. A substitute teacher was instructing the class, students said.
Many students, like senior Areeb Ahmed, said they believed the evacuation of the school was a drill considering Wednesday's balmy weather.
"We didn't know what was going on. We thought it was a fire drill," Ahmed said. "And then we saw the ambulances and the fire trucks coming with their lights on, so we knew it was real."
Fire officials could not immediately provide the ages or genders of the students who were hurt, but the classmates said the injured students were all sophomores.
The vice principal called a school assembly after students were let back into the building and said the injured students were "all doing fine," Ahmed and other students said.
Freshman Laura McGinn said she was just across the hall from where the incident happened when she heard a girl "scream."
"It was a scream right before the fire bell went off," McGinn said. "I was like 'what's going on?'"
McGinn said the term "explosion" was probably an exaggeration. Emma Johnson-Geis, a senior, was eating lunch with friends in the hallway next to the chemistry lab when she heard a "burst."
"It wasn't very loud," she said, adding a stream of students rushed out of the room soon afterwards. "They were definitely all really scared."
Johnson-Geis said the students were using a Bunsen burner to cook food in the lab and said the room was ideal for a cooking class.
"It normally works out great because it's a nice, sterile environment, but in this case it backfired, quite literally," she said.
Chicago Public Schools spokesman Joel Hood said the incident, which happened during "routine cooking instruction" on a single-burner stove, was being investigated.
Officials said the cause of the accident was unclear, but that there was no damage to the building.