Nearly a dozen Brooklyn students were exposed to pepper spray and required emergency attention Monday, police say.

Just after 1 p.m., police say students at I.S. 252 began coughing, with one even throwing up due to exposure to the pepper spray.

Sources say a 13-year-old girl had a small canister around her neck, and that it went off on her classmates when she bent forward underneath a table.

Eleven students were treated in total, all of whom are expected to be OK. They were either released to their parents or brought to Brookdale Medical Center.

Sources say the 13-year-old in possession of the pepper spray will have a juvenile report, but not a criminal record, from this incident.