The threat that prompted Los Angeles Unified School District officials to close all schools Tuesday appears to be a hoax, a U.S. congressman on the House Intelligence Committee said, reports the Los Angeles Times .

"The preliminary assessment is that it was a hoax or something designed to disrupt school districts in large cities. The investigation is ongoing as to where the threat originated from and who was responsible," Rep. Adam Schiff (D-Burbank) said in a statement.

Another local congressman, Brad Sherman, said the person who sent an email threat to several Los Angeles Unified School board members claimed to be the victim of bullying and "an extremist Muslim who has teamed up with local jihadists" — although showed no real knowledge of Islam.

"There isn't a person on the street who couldn't have written this," said Sherman, a senior member of the House Foreign Affairs Committee.

The email also mentioned explosive devices, assault rifles and pistols and was traced to an IP address in Frankfurt, Germany, according to law enforcement sources. But it could have been used to mask the sender's true location.

NYPD received a similar threat but decided it was not credible.

LAPD Chief Charlie Beck said his agency reviewed the threat before contacting the FBI. He called any criticism of the school closures "irresponsible" at this point.

"Southern California has been through a lot in the past few weeks," he said. "Should we put our children through the same thing?"