A student discharged pepper spray in a bus full of children in Allied Gardens on Wednesday, according to a school district spokesperson.
At around 2:30 p.m. a student discharged pepper spray on the bus transporting 60 children from Lewis Middle School at the intersection of Waring Road and Zion Avenue.
Everyone was then removed from the bus, according to San Diego Unified School District spokesperson Jack Brandais.
Three children and the bus driver were transported to a local hospital complaining of difficulty breathing.
The student is in custody. SDUSD has a a zero tolerance policy for punishment, and the student could face expulsion, said Brandais.
Keep up to date on breaking news: Download our improved iPhone app, follow us on Twitter @nbcsandiego, fan us on Facebook, sign up for our breaking news e-mail alerts or text SDBREAKING to 622339 to receive text messages for local breaking news. (For more info, text HELP. To end, text STOP. Message and data rates may apply.)