Los Angeles Unified School District Superintendent Ramon Cortines ordered all schools be closed Tuesday morning after receiving a "credible threat" of violence to some 640,000 kindergarten through 12th grade students.
"It was not to one school, two schools or three schools. It was many schools, not specifically identified. But there were many schools. That's the reason I took the action that I did," Cortines said during a press conference. "(The threat) was to students at schools."
Cortines immediately notified law enforcement after receiving the electronic threat late Monday night. Officials confirmed references to assault rifles, machine guns, backpacks, and "other packages," though they questioned its validity.
New York City officials said they received the same email, as did many school districts nationwide, but quickly determined it was a hoax. It routed through Germany but its direct origin is unknown.
NYPD Commissioner Bill Bratton, who used to serve as Los Angeles' police chief, said the threat was "specific but non-credible," pointing out grammatical errors a devout jihadist would not make; an example given is the misspelling of Allah, with was written a lowercase A.
"These threats are made to promote fear. ... We cannot allow us to raise the levels of fear," Bratton tweeted. "We are very comfortable that this is not a credible threat."
The New York Department of Education and LAUSD carry the largest school districts in the country, respectively, yet raised different concerns when it was time to notify parents.
New York City Mayor Bill de Blasio said shutting down schools would be "a huge disservice to our nation." Cortines cited an unwillingness to "take the chance with a life of the student."
The superintendent directly referenced the Dec. 2 mass shooting in San Bernardino that left 14 people dead and 22 others injured. The Inland Regional Center sits about 60 miles from Los Angeles where many of the victims either lived or had families.
Given the proximity of that attack and the frequency of school shootings, current LAPD Police Chief Charlie Beck believes school district officials made the right call.
"This school district safeguards three-quarters of a million lives every day," Beck said. "I think it's irresponsible to criticize that decision at this point. These communities have been through a lot in the recent weeks."
As to who orders a closures depends on who's in control.
New York schools are under mayoral control, leaving de Blasio decide whether some 1.1 million students missed class.
"We've come to the conclusion that we must continue to keep our school system open," De Blasio said Tuesday morning. "(It is) very important not to overreact to situations like this."
Cortines didn't have to consult LAPD officials before issuing an order a closure of 900 schools and 187 public charter schools. Los Angeles Mayor Eric Garcetti said it wasn't his decision to make, but one he could support.
"It's easy for people to jump to conclusions," Garcetti said. "But decisions need to be made in a matter of minutes."