Authorities have determined that the suspicious objects found at Sierra Middle School in east Bakersfield were water bottles containing a small level of acidity.

The Kern County Sheriff's Department Bomb Squad and county Environmental Health officials responded to a call of a small explosion at the school Monday morning. Sheriff's spokesman Ray Pruitt said there was in fact no explosion, but that the cap of a swollen plastic water bottle popped off and some liquid sprayed out after a teacher unscrewed the cap to relieve pressure.

The teacher had been recycling the bottles at the school when she noticed that two of them were swollen, Pruitt said. The teacher noticed a chemical odor when the cap popped off and notified the principal, who then called authorities.

Classes were in session and there was no danger to students or teachers, Pruitt said. It's unknown what caused the acidity in the bottle.

The teacher was hit by some of the spray but was not injured and did not require medical attention.

Anyone with information is asked to call the Kern County Sheriff's Department at 861-3110. Anonymous text tips can be sent to TIP411 (847411); just type the keyword "KCSO" prior to the message.