School officials heard a rumor Wednesday and sprang into action investigating it.
The rumor was that a shooting would take place Friday at Pleasant Grove High School.
The rumor spread throughout social networking sites as Elk Grove Unified School District Police and the Sacramento County Sheriff's Department investigated, district spokeswoman Liz Graswich said Friday.
"They were unable to find the source of the rumor and they determined the rumor was unsubstantiated," Graswich said.
Authorities completed their investigation Thursday and were able to send a message to parents notifying them the district had looked into the rumor and found it to be without merit, she said.