A chemical spill at East Valley High School in North Hollywood, Calif., caused the entire campus to be evacuated and four people to be sent to the hospital, KABC-TV reports.

According to the station, a chemistry teacher accidentally mistook sulfuric acid for nitric acid -- causing dangerous redish-brown fumes to fill the room. The teacher, along with another female teacher and two other students were sent to the hospital that afternoon and a hazardous materials team was brought it in contain the fumes.

The Los Angeles Times reports part of a North Hollywood street was also closed and around 15 students were examined by the Fire Department.

No one was seriously hurt from the incident, and Brian Humphrey, spokesman for the Los Angeles Fire Department, told the Los Angeles Daily News the teacher reacted to the spill appropriately.

"The teacher quickly covered the container and placed it under the vent," Humphrey told the paper. "She calmly evacuated her class. She is to be commended in her actions."