The police raided the apartment of the teenager’s family on Thursday morning and arrested him as the prime suspect behind a monthslong wave of bomb threats against Jewish institutions in the United States, Australia and New Zealand, sowing panic and prompting evacuations. The Israeli police said he had also made threats against commercial airlines, including at least one Delta Air Lines flight in 2015, forcing an emergency landing.
The suspect has remained publicly unidentified because of a court-imposed order of silence forbidding the Israeli authorities from naming him, at least until his next court hearing on March 30. But the bizarre nature of the case and the immediate lack of any clear motive or explanation only compounded the bad feelings here.
The accused’s lawyer described him as a home-schooled computer fanatic who had a brain tumor that could affect his judgment. The suspect’s father, an engineer in his early 50s who also has not been publicly named, was detained on suspicion of involvement in the threats, though his lawyer said he had no knowledge of them. The mother of the teenager, who had no siblings, had by all accounts switched off her cellphone and could not be found.
The arrest came after months of investigation by the cyberunit of the Israeli police, in cooperation with the Federal Bureau of Investigation and other foreign police and security agencies. The Israeli police seized computers, an antenna and other equipment from the family’s apartment and said the calls had been made through the internet, using software to disguise the suspect’s location and voice.
The family moved about two years ago into a modern apartment block in the upscale, beachside neighborhood of Barnea, one of a row on a residential street sprinkled with single-family homes, gardens and a small neighborhood synagogue.
“This is an expensive neighborhood, exclusive,” said Etty Shekel, a neighbor who lives in one of the three apartments on the raided apartment building’s fifth floor. Ms. Shekel, 47, runs her own plant nursery, and her husband, Rafi, works in the Ashdod port.
She said her family — including two sons, 19 and 21, who serve in the military — had had almost no contact with the neighbors who had been arrested. “There was no interaction,” she said. “He was not a regular boy.”
Unlike most Israeli Jewish young men, the accused was not drafted into the military at 18. The army said it had rejected him as unfit to serve; the suspect’s lawyer said that was because of his medical condition.
Ms. Shekel described the parents as ordinary and quiet. She said she believed that the father was a native of Ashkelon and the mother a Westerner, presumably from the United States. “I’m pleasant to people, I say hello when I meet them,” she said. “But I don’t go knocking on neighbors’ doors or poke our noses into other people’s houses.”
After they moved in, the neighbors brought the Shekels a traditional gift of food for the Jewish festival of Purim, and the Shekels reciprocated with a potted plant at Passover. “That was the extent of our neighborly relations,” Ms. Shekel said.
One of her sons, home from the army for the weekend and waiting outside the building for his friends to pick him up, said he had seen the suspect only a couple of times. “Wow, he was really just one meter away from me!” he said.
Ashkelon, a city of around 130,000 residents, has a vibrant community of English-speaking immigrants who came from Britain, South Africa and the United States. But residents said they could find no trace of the family on local internet forums for English speakers, and the family did not appear to be listed in the telephone directory.
Beverley Jamil, who moved to Ashkelon from Manchester, England, in the 1980s, said many of the teenagers in the city knew one another from school, Scouts or other social activities. But she said her 19-year-old twin daughters had never come across the suspect.
Avi Meir, 29, who works in the Tel Aviv Stock Exchange, said that over the past few days he had spotted police lookouts on the rooftops staking out the apartment building to the left of his. He had assumed they were there for another neighbor who, he said, was known to the police.
Shalom Malka, 61, a retired truck driver who lives in the building to the right of the suspect’s, joked, “I didn’t know there were such clever people in Ashkelon!” He then suggested that the police recruit the suspect to help out in their cyberunit.
But when he considered the damage the hoax caller had done to the Jewish communities abroad, his tone abruptly changed. “It’s a disgrace,” he said. “The guy is a fool.”