A hoax is being perpetrated on schools across the country, threatening an attack, as part of an online game.
Many Bay Area districts have been targets.
Emeryville canceled Monday classes as a precaution. The threat was e-mailed to Emeryville's superintendent at about 10:30 p.m. Sunday, leaving little time to evaluate it.
By Monday, a pattern was emerging, as the identical threat showed up in dozens of inboxes.
"Our understanding is it was a mass mailing to school districts throughout the United States," said Captain Oliver Collins, of the Emeryville Police Dept.
Dozens, possibly hundreds of school districts in 46 states were apparently targets.
The email purports to be from a bullied student who is threatening bombings and gunfire. "The threat is that someone was going to come to the school and shoot students and faculty at the school." said Capt. Collins.
At the Piedmont Unified School District Offices, the email hit Superintendent Randall Booker's mailbox at mid-morning.
"It was a few sentences but very graphic," Booker told KTVU. He had already heard from colleagues in Alameda County that there was a hoax circulating.
"When we received ours, I knew something was going on but it was still disconcerting," said Booker.
Responsible for 3,000 students and staff, Booker talked to Piedmont's Police Chief before proceeding with a normal school day.
"It didn't name anything specific, no specific buildings, no specific people, a time, date, any of that," Booker explained.
By afternoon, school districts across the Bay Area were issuing statements to their communities. Livermore Schools' statement read in part "this e-mail is from an international hacking group that has sent similiar emails to schools in the United Kingdom".
In fact, it appears to be a competition among online gamers to see who can cause the most school evacuations in Britain and the United States. The senders are likely overseas.
"I just wish people would use their energies for good things and not bad, it would make the world much better," reacted parent John Cmelak, of Castro Valley.
"It's unfortunate and sad," said parent Giselle Levy, "and I don't want our kids growing up in this, but this is what the world has come to."
The FBI is investigating, and confirms the e-mails "appear to be part of a larger influx of threats and they do not appear to be legitimate."
"I think it's terrible," said Capt Collins, "and for a community as small and close as Emeryville, it impacts us greatly."
Emeryville will post officers at its K- through- 12 campus Tuesday morning, visible reassurance for students returning from spring break a day late.
Since Florida's school massacre, there has been a heightened sense of vulnerability- and a surge in false threats- with evacuations and lockdowns keeping school communities on edge.
"It's much more than a distraction, it's a crime," said Superintendent Booker, who notes educators resent anyone exploiting the current climate for their own amusement.
"This isn't a game, we're talking about people's lives, and we're talking about the innocence of children, because schools are a safe haven."
The hoax is believed to have started in Switzerland, although some point to origins in Ukraine.
The disruption to schools might have been even more widespread, but many of the e-mails went into spam fles, and were not noticed immediately.