(CNN) Anonymous bomb threats to Jewish institutions have spiked to about 140 incidents across the country since January, according to the Anti-Defamation League. Here's what we know:When it beganSince January, Jewish community centers around the country -- even ones in Canada -- have received bomb threats. Six waves of threatsBomb threats against Jewish institutions in 2017 1st wave of threats (Jan. 4 -11): 20 incidents 2nd wave of threats (Jan. 17 - 18): 27 incidents 3rd wave of threats (Jan. 31 - Feb. 9): 17 incidents 4th wave of threats (Feb. 16 - 24): 17 incidents 5th wave of threats (Feb. 27): 40 incidents 6th wave of threats (March 3 - 7): 15 incidents Source: Anti-Defamation LeagueThe ADL says there have been six waves of bomb threats against Jewish institutions this year. One arrest made so farA former reporter was arrested in St. Louis and accused of making some of the recent bomb threats against Jewish institutions. The accusation against Thompson accounts for just a small minority of more than 100 total bomb threats on Jewish institutions.

Source: CNN March 08, 2017 08:18 UTC