WASHINGTON (JTA) – Bomb threats were called in to at least 16 Jewish community centers and other institutions in seven states on Monday, Jan. 9. 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, said Paul Goldenberg, the director of Secure Community Network (SCN), the group affiliated with the Jewish Federations of North America that coordinates security for the Jewish community. The states were spread across the South and the Northeast. Only some of the JCCs were evacuated. All the alerts were false, Goldenberg said, and designed to produce maximum disruption. He did not name the states or JCCs, but various media have reported bomb threats in Florida, Maryland, Tennessee, South Carolina and New Jersey. As of 4:30 p.m. Monday, most of the JCCs resumed regular operations.

Among the affected sites were the Kaplen JCC on the Palisades in Tenafly, New Jersey, the Miami Beach Jewish Community Center and Alper JCC in southwest Miami-Dade, the Siegel JCC, north of Wilmington, Delaware, the preschools at the Tampa JCC and the Tampa Jewish Federation in central Florida, and the Jewish Community Alliance in Jacksonville, in northern Florida. All the facilities were evacuated, searched and given the all-clear by authorities.

Goldenberg counseled an immediate call to local first responders in every instance, but also said live calls indicated a more acute risk than robocalls. He also recommended studying a 15-minute video that SCN has posted on its website outlining what to do in case of a bomb threat. Goldenberg said SCN in the next few days would organize, through the JCC Association of North America, a conference call reviewing possible threats.

In London, bomb threats were called in Monday to three Jewish schools, the Jewish Chronicle reported. Searches of the schools did not turn up any explosives, and other schools in the area were placed on lockdown until the searches were completed. Copycat calls reportedly also were made to several non-Jewish schools.

Bomb threats were also called into two Jewish institutions in the Orlando, Florida, area on Jan. 5.

There has been an increase in the United States in reports of threats and vandalism on Jewish property in the wake of the presidential election. President-elect Donald Trump, who was reluctant to denounce support during the campaign from white supremacists and anti-Semites, has since repudiated racists who say they feel emboldened by his victory, as well as ultranationalist successes in Europe.