(Reuters) - A rash of email and phone threats of violence hit schools from New Jersey to Florida to Texas on Thursday, but most were deemed to be hoaxes and schools opened.
However, two suburban Indianapolis school districts in Danville and Plainfield shut down due to threats over social media. Overnight, two Danville high school students were arrested, accused of apparently unrelated threats.
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Officials were on heightened alertness after the deadly attacks in San Bernardino, California, on Dec. 2. On Tuesday, Los Angeles shut down schools over emailed threats that later deemed a hoax.
School districts in Houston, Dallas, Orlando, Fort Lauderdale and Miami all decided on Thursday that emailed threats were not credible, and were similar to ones sent to schools in New York City and Los Angeles earlier this week.
Meanwhile, an all-clear was given after East Orange Campus High School in New Jersey was evacuated on Thursday following a phoned-in bomb threat.
Anacostia High School in Washington, D.C., was evacuated before 12:15 EST over a suspicious package that was still being investigated.
"MORE OF A LOCAL SITUATION"
The Indiana threats appeared to be different from the hoax emails sent to the larger school districts elsewhere in the country, Danville Community School Corporation Superintendent Tracy Shafer told Reuters.
"This seems to be more of a local situation and the perceived threats were posted to social media and were specific to our schools," Shafer said.
Earlier, Danville Police Chief William Wright told reporters at a news conference that two Danville Community High School students, a freshman and a senior, were arrested after midnight on Thursday "due to threats received through social media."
He said the two juveniles could be charged with intimidation and other crimes. "Get ready to go to jail," he said. "We're flat out not going to put up with it."
Wright and Shafer both said that further threats were made on Facebook after the arrests, apparently by another person. The later threats involved schools both in Plainfield and Danville, prompting both districts to shut schools on Thursday.
Plainfield has six schools and about 5,400 students, while Danville has four schools and about 2,500 students.
FLORIDA, TEXAS THREATS NOT CREDIBLE
School officials in Texas and Florida said they increased school security to be on the safe side.
"At this time, we do not believe the threat is credible, but as a precautionary measure, law enforcement officers are in the process of conducting random sweeps of school district buildings to ensure student safety," the Houston Independent School District, with about 215,000 students, said in a statement.
In a move criticized by some law enforcement officials as an overreaction, officials in Los Angeles, the nation's second-largest school district, canceled classes for 640,000 public school students on Tuesday over a threatened attack with bombs and guns that was later deemed a hoax.
New York City officials said they received a nearly identical threat to public schools but dismissed the message and kept schools open.
A spokeswoman for Broward County Public Schools in South Florida said the district's police department immediately communicated an emailed threat it received late Wednesday to federal, state and local law enforcement agencies.
"At this juncture, the threat is deemed as less than credible," said Tracy Clark, school district spokeswoman, adding additional security had been deployed to schools as a precautionary measure. The district has more than 265,000 students.
The Dallas Independent School District, with approximately 160,000 students, also said it would keep schools open.
"Someone is trying to scare Dallas. It's not going to work," Dallas Mayor Mike Rawlings said at a news conference on Thursday.
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