The likelihood that threats to unleash five assault rifle shooting attacks in the San Gabriel Valley were phoned in by the same malicious hoaxster is being pursued by investigators from three police agencies, the LA County Sheriff, and the FBI, officials said.
Three of the calls said schools would be targeted.
One call mentioned Citrus Valley, a family of hospitals with four campuses in three cities. Also now being investigated as potentially part of the same wave of threats is a call placed Tuesday evening to security at the Westfield Santa Anita Mall in Arcadia.
The caller said he was armed with an AK-47.
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"The caller also stated he was going to enter the mall and shoot people," according to a statement issued by the Arcadia Police Department.
The investigating agencies are now pooling information, Arcadia Police Lt. Roy Nakamura said Friday.
Making a terrorist threat is a crime itself under state and federal law, even if there is no intent to carry it out.
The schools named in the threatening calls were placed in lockdown while law enforcement searched for evidence of a shooter. None was found at any of the schools, or at the hospitals, or at the mall.
Santa Fe Middle School in Monrovia was the first to be affected on Monday. Tuesday in Duarte, a lockdown affected both Duarte High School and adjacent Northview Middle School. The most recent threat to a school was called in Thursday afternoon to Arcadia police dispatch and named Arcadia High school.
The caller "said he had an assault rifle and was going to start shooting students on campus," Nakamura said.
Administrators received word from police just minutes before the scheduled 2:45 p.m. final bell, and responded before the bell rang. It meant that students, faculty and staff were unable to go home, but instead huddled in rooms with lights turned off for nearly four hours before searching police sounded the all clear.
At one point during the lockdown, another call – believed to have been from the same man who made the initial threat – demanded officers back off, or risk being shot, according to police.
"This guy is getting off trying to scare people," said an Arcadia High School junior who was in her AP Calculus class when the lockdown began. She is also involved on campus with the production of "Apache News," the school's own newscast, and interviewed fellow students and recorded video on her iPhone to be used in her report on the incident.
"I cannot imagine the kind of person who would do this to students," said Brent Forsee, EdD, principal at Arcadia High School, which has a reputation for academic excellence.
The school cancelled Thursday’s back to school night, but on Friday returned to normal campus schedule and events, including a luncheon recognizing its 22 National Merit semi-finalists. The school recently had gifted its students with "I (heart) Arcadia" buttons meant to be passed on to individuals who show good character. Thursday evening, after the emergency was deemed over, many students awarded their buttons to the officers who had responded.
Dealing with threats has become an unfortunately recurring aspect of education. The AP Calculus student recalled that this was the fourth lockdown she has gone through since middle school.
During Thursday's lockdown, she said, students were more frustrated than fearful. But concern triggered by the threats has affected at least one other San Gabriel Valley school.
A parent at San Julian Elementary in La Puente expressed anxiousness about the incidents, prompting a call to LA Sheriff's Industry Station. A dispatched patrol unit found no problem and school resumed, according to principal Martha Arceo.
She and the sheriff’s department emphasized there had been no threat made.
Later Friday, to the east in Fontana, Mango Elementary School was evacuated after a bomb threat. Nothing was found.
Initial indications show no connection to the gun threats in the San Gabriel Valley, according to an FBI source who had been briefed on the Fontana case.
For law enforcement, tracing back phone calls is tougher in this age of disposable black market cellphones and voice over internet calls.
How far investigators have gotten in locating the sources of the calls, authorities declined to discuss.