A man has been arrested in Israel on suspicion of making bomb threats against Jewish community centres in Australia, the United States and New Zealand over the past three months.
Sources familiar with the case gave the suspect's age as 19 and said he is Jewish and holds Israeli and US citizenship.
Police spokesman Micky Rosenfeld said on Thursday that the suspect's motives are unclear.
Mr Rosenfeld says the suspect is "the guy who was behind the JCC threats," referring to Jewish community centres that have received dozens of anonymous threats in recent weeks.
Rosenfeld says the man, from the south of Israel, used advanced technologies to mask the origin of his calls and communications to synagogues, community buildings and public venues.
He says the investigation was carried out with the help of the FBI and police from other countries.