Hundreds of members of the Jewish communities across the United States evacuated at least 16 community centers in six states following he issuance of bomb threats against them.

Citing a New York NBC affiliate, the Times of Israel reports that threats had been received throughout the eastern United States: Miami Beach and Jacksonville, Florida, South Carolina, Nashville, Tennessee, Rockville, Maryland, and New Jersey.

Authorities were also investigating a bomb threat in California.

“The calls were prerecorded in some cases and live in others, with the caller using voice disguising technology, and likely came from a single source,” indicated Paul Goldenberg, the director of Secure Community Network, the group affiliated with the Jewish Federations of North America that coordinates security for the Jewish community, according to the Times of Israel.

Although Goldenberg said all the alerts were false and intended to produce maximum disruption, news outlets acknowledge it is not yet clear whether all the calls have been determined to be a hoax.

At least in Tennessee, the Tennessean reports, “Police determined the threat was a hoax and about 12:20 p.m., police gave the all clear and allowed people to return inside the building, Mark S. Freedman, executive director of the Jewish Federation of Nashville and Middle Tennessee said.”

Nevertheless, Freedman said,“We’ve taken all the necessary precautions that you would in a situation like this,” adding, “This is a threat against the entire community. Everyone should be aware of that.”

“Similar threats were phoned in to several Jewish schools in Britain. Community officials responded by sending out a national alert that saw emergency procedures implemented at some institutes,” points out the Times of Israel.

In Miami, two Jewish community centers had been evacuated after calls around 11:00 a.m.

Meanwhile, a call, reportedly from a local number, prompted an estimated 300 children from one of the facilities — Dave and Mary Alper Jewish Community Center — to evacuate to a nearby tennis court.

“JCC MetroWest in West Orange [New Jersey] sent an email to members about its enhanced security protocol, which includes moving its guard post to a more visible location, rotating guards on patrol and installing new, brighter lighting in the garage,” reports the New York NBC affiliate.

“We know of NO immediate threat to our JCC, we have made these adjustments as part of our ongoing effort to consistently review our security program and put in place the recommendations of well qualified security professionals,” declared the email.

According to the Britain-based Jewish Chronicle daily, schools in Roehampton, Ilford and Brent, all in London received threats by telephone.

“Police were alerted at around 10:30 a.m. on Monday, 9 January, to phone calls made to schools in Roehampton, Ilford and Brent, in which bomb threats were made,” noted the Metropolitan Police.

“Police officers attended the schools. All three incidents were stood down a short time later. An investigation into the threat will be conducted,” it added.

In the U.S., the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) is aware of the threats and has offered assistance to local authorities if necessary, spokeswoman Amanda Hils said told Reuters.