SAN FRANCISCO (CBS SF) — The San Francisco Unified School District was among school districts across the country to receive email threats similar to those received in Los Angeles and New York earlier this week.

SFUSD said Thursday in a statement that the district and the city have coordinated with local and federal agencies to determine the risk and that nothing suspicious was found after the schools were inspected. “At this time, we do not believe the threat is credible, but as a precautionary measure we have increased police presence around schools and transit corridors to and from schools,” the statement said.

Across the U.S., school districts announced news of “less than credible” threats were received by email late Wednesday evening, and that schools would be open Thursday. Most school districts said classes would go on after campus inspections; however, two school districts in Indiana did cancel classes after also getting threats.

Some of the nation’s largest school districts such as Miami, Ft. Lauderdale, Houston and Dallas received threats. “We need to make sure that we don’t overreact to fear,” Dallas police Chief David Brown said.

Dallas Mayor Mike Rawlings agreed, adding, “Obviously someone is trying to scare Dallas and that is not going to work.”

Robert Mock, police chief for the Houston Independent School District, said random overnight searches by explosives detecting dogs and patrol officers turned up nothing after district officials, including the superintendent, received the threat by email.

So far Thursday morning, “everything’s been normal, schools are in session, kids are learning,” Mock said.

He added that he doesn’t want to downplay the message because “a threat is a threat.” But he said the message referred to weapons and explosives among unsophisticated content that was “so far over the top the logistics just didn’t pan out.”

On school district websites, officials said the threats were similar to those received in New York and Los Angeles earlier in the week. Los Angeles, which has the nation’s second-largest school districts, closed Tuesday after receiving the threat. Officials in New York determined the threat was a hoax and kept schools open that day.

It’s rare for a major U.S. city to close all its schools because of a threat and the closures in Los Angeles reflected the lingering unease in Southern California following the attack that killed 14 people at a holiday luncheon two weeks ago in San Bernardino.


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