After a threat hoax closed down all Los Angeles Unified School District schools, disrupting families across Los Angeles, school officials said they planned to reopen campuses on Wednesday.
All schools in the LAUSD, the nation's second largest, were closed Tuesday morning after a threat mentioning explosive devices and weapons was emailed to the district, according to the district and police department.
A preliminary investigation suggests the threat — and a similar one sent to New York City schools — was a hoax, according to a statement from Rep. Adam Schiff, the ranking member of the House Permanent Select Committee on Intelligence.
"The preliminary assessment is that it was a hoax or something designed to disrupt school districts in large cities," Schiff said in a statement. "The investigation is ongoing as to where the threat originated from and who was responsible."
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The email message was delivered to "a number of people on the school board" and implied a threat of "explosive devices, assault rifles and machine pistols" to all LAUSD campuses, Los Angeles Police Chief Charlie Beck said.
Law enforcement sources told the NBC4 I-Team that the email threat was received at 10:15 p.m. PT Monday, leading to a closure that affected hundreds of thousands of students and their families.
The email was routed through Germany, but investigators have not determined its origin and believe it was sent from a location "much closer," Beck added.
Supt. Ramon Cortines said the closure in the nation's second-largest school district — which serves 640,000 students — was out of "an abundance of caution."
"I am not taking a chance of bringing children into a place, into any part of a building, until I know that it’s safe," Cortines said. "I, as superintendent, am not going to take the chance with the life of a student."
Schools will not reopen until authorities are "completely satisfied that we have taken every measure to ensure the safety of our students," according to school police Chief Steven K. Zipperman.
The districtwide closure was likely an unprecedented step. District personnel said they are checking records to determine whether all schools have ever been closed for an entire scheduled school day due to a threat.
"I was literally in shock," said Virgil Middle School teacher Claudia Castaneda. "Ten years working for LAUSD, and I never had such an experience. I am concerned that this is going to be the norm from now on."
School police said the FBI was notified and the threat is being analyzed. The FBI confirmed the agency is providing resources for the investigation, which includes a districtwide search by law enforcement agents, a sweep that will likely take the rest of the day because of the district's size, Cortines said.
Officials in New York City said schools there received the same anonymous threat but deemed it "not credible" and were investigating the email as a hoax. New York Mayor Bill de Blasio and Police Commissioner Bill Bratton said several other districts nationwide also received an email threat, but investigators determined students weren't in any real danger.
Bratton, Los Angeles' former police chief, said the person who wrote the note claimed to be a jihadist, but errors made it clear the person was a prankster. Police in New York said the sender behind both threats claimed to be a high school senior, law enforcement sources told NBC New York.
"There was nothing credible about the threat. It was so outlandish," de Blasio said.
When asked at a morning news conference why the LAUSD took action, Cortines described the threat as "rare." He said the area is on heightened alert in the wake of a mass shooting that left 14 dead and wounded 22 in San Bernardino earlier this month.
"I think the circumstances in neighboring San Bernardino, I think what has happened in the nation, I think what happened internationally" influenced the decision, Cortines said.
Beck and Mayor Eric Garcetti defended Cortines' decision to order a districtwide closure, which comes a week before LAUSD's winter recess.
"It's not (my decision) to make, but it is mine to support," Los Angeles Mayor Eric Garcetti said during a news conference Tuesday. "It's easy for people to jump to conclusions. But decisions need to be made in a matter of minutes."
LAUSD schools are closed today due to credible threat. Updates will be provided via https://t.co/AZDfmuaMmu & 213-241-2064.— LAUSD (@LASchools) December 15, 2015
Superintendent: every school being searched by appropriate personnel.— LAUSD (@LASchools) December 15, 2015
Board president: all students are safe.— LAUSD (@LASchools) December 15, 2015
LAUSD enrolls hundreds of thousands of students in kindergarten through 12th grade at more than 900 schools. The district covers about 720 square miles in Los Angeles and smaller Southern California communities.
"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. ... The threat was very specific to LA Unified. These are very high stakes. There is no more important decision."
Parents told NBC4 they were notified early Tuesday that they should not send students to school. All students already at school Tuesday morning were sent home, Los Angeles School Police said.
"I literally woke up to the call," said parent Jim Alger. "There's this element of fear. Things like this are kind of reminiscent of the post-9/11 days. But I guess it's better safe than sorry."
But some parents told NBC4 they did not receive an alert from the district's emergency notification system. Others said they were notified at different times.
The system, called Blackboard Connect, uses a system in which parents fill out a contact form with phone numbers and email addresses. NBC4 reached out to the company and district for comment.
The district also tweeted information about the closure and activated an information hotline for parents at 213-241-2064, which was temporarily taken down reports that it was not functioning.
Link: LAUSD FAQ
Students at some schools said they initially thought the threat was part of a finals week prank.
Metro buses and trains provided free rides to LAUSD students until noon, according to the mayor's office. The Petersen Automotive Museum in the Miracle Mile District offered free admission to students.
No closures were reported at nearby school districts.
NBC4's Nyree Arabian contributed to this report.