But some school leaders aren't taking any chances with their students. The FBI is now working with local law enforcement to investigate the threats.
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Emery High was closed Monday as were all the district's schools after the superintendent received an email that ABC7 News is told said something about a student in need of help who had been bullied.
It turns out the email was part of an online competition to close schools.
There were squad cars in the parking lot, locked doors, and an empty campus after a threatening email containing a claim to shoot students and faculty was sent to Emeryville.
Classes were canceled.
"It was the right decision at the right time," said Captain Oliver Collins with Emeryville police. He says his detectives started investigating as soon as the threat came in at 10 p.m. Sunday night.
RELATED: FBI says online hoax threatened violence at several Bay Area schools
By Monday morning police determined it was a hoax that originated in an online gaming community. More than 50 Bay Area school districts received the threatening email, many of them were just coming back from spring break Monday morning. By the time officials saw the email, Emeryville police and other law enforcement agencies determined that it was not a credible threat, so they kept schools open.
"It's not a good situation," said Michelle Smith McDonald who works for the Alameda County Office of Education. "Schools are making tough choices."
Thirteen of their school districts including Dublin received threats.
"The idea that this was a dare or some sort of bet where they wanted to frighten and alarm school communities," added McDonald. "It's really troubling."
Parents at Glenview Elementary in Oakland were alarmed to learn their schools were also threatened. Many feel canceling class in Emeryville was unfortunate but in the end a smart decision.
Below are the school districts that ABC7 News has confirmed were affected:
Alameda County School Districts:
Officials say at least 13 of the 18 Alameda County School Districts received the email on Monday. All immediately reached out to local law enforcement.
San Mateo County:
The county confirms that the San Mateo County Office of Education, the county superintendent and Cabrillo Unified School District received hoax emails Monday morning. They say that is only one district of 23 in the county, and about half the schools are on spring break and operations were not disturbed there.
Contra Costa County:
The county says at least nine of the 19 districts received a hoax threat email. Parents were contacted by all districts.
Officials did not give a specific number, but the Office of Education says that "many" of the 40 school districts in the county were threatened. They provided more information here.
Oakland Unified School District:
The school district says they received at least one of these emails but it did not disrupt normal school operations.
San Ramon Valley Unified School District:
Brentwood Unified School District:
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