HONOLULU (AP) — A can of pepper spray went off inside a plane headed from Oakland, California, to Maui on Friday, requiring emergency help for several people aboard, Hawaiian Airlines said.

Twelve passengers and three flight attendants were treated for respiratory issues and released by emergency responders at the airport in Kahului, Hawaii, airline spokesman Alex Da Silva said.

A passenger illegally brought the pepper spray on the plane carrying 256 passengers and 10 crew members, but it appears it discharged accidentally, Da Silva said in a statement. The airline could not provide any details about the passenger or why they believe the release was accidental.

The flight crew of the Boeing 767 declared an emergency to get priority at the airport in Hawaii.

Cory Lum/Civil Beat

About 30 people complained of being affected by the irritant, but no one was taken to the hospital, Hawaii Department of Transportation spokesman Tim Sakahara said.

The airline said the flight was delayed earlier Friday after a teenager in Oakland sent a photo depicting a fake crime scene “featuring a child-sized mannequin” to other passengers’ cellphones. The teen and his family were booked for a later flight while officials investigated.

Hawaiian Airlines said the two incidents were not related and the family’s baggage had to be located and removed from the plane, causing the delay.

The Federal Aviation Administration said in an emailed statement that it could not confirm what the substance was but that pepper spray is prohibited on planes. The agency can take legal action against anyone who violates federal aviation regulations.

Officials with the Transportation Security Administration, which screens carry-on baggage, and the National Transportation Safety Board did not immediately respond to requests for comment.

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