Noam Rotem and Yuval Adam, two researchers operating the Big Bots Project, said in a report that they uncovered hundreds of fake accounts spreading messages in support of Netanyahu's Likud party and smearing his opponents. Likud denied the allegations.
Adam said his project discovered a network that included a number of real people, along with hundreds of Twitter accounts that appeared to be fake or duplicate. "One person might be operating tens or hundreds of accounts at the same time," he told The Associated Press. "All these accounts are pushing their political agenda, not only that but also inciting hate speech, attacking very specific people who are opposed to their political agenda."
Israelis head to the polls in eight days in a close race between Netanyahu and his main rival, former army chief of staff Benny Gantz. Netanyahu is seeking a fifth term in office under the shadow of corruption charges.
The campaign has focused largely on personal attacks between the two front-runners, with Gantz taking aim at Netanyahu's alleged ethical lapses, and Netanyahu painting Gantz as a weak "leftist." The prime minister's Likud Party has also tried to portray Gantz as being mentally unstable.
Rotem and Adam said they found no direct link between the network and Netanyahu or Likud. But Netanyahu's son Yair, who has run into trouble in the past for controversial social media activity, has frequently liked posts by the network's accounts.
They said it was unclear who was operating the network. The report said the network had relayed tens of thousands of tweets and garnered over 2.5 million engagements. Many of the accounts in the network were largely inactive before elections were announced in December. Since then, these users have tweeted frequently and exclusively about the Likud party and against its opponents, Adam said.
The report found a huge spike in activity during the first few months of the year compared to the same period in 2018; for example, March 2019 had 13.2 times more average activity than in the same month last year.
One of the most active Twitter accounts mentioned in the report became private shortly after the 34-page document was published, Adam said. At a press conference convened to address the issue, Netanyahu dismissed the report sarcastically as an April Fool's Day prank. He called it a "false libel" by the media based on a "fake investigation."
"Almost all of the examples, perhaps all of them, turned out to be real people. They have a name, they have a face, they have families, and the worst thing: they have opinions of their own. Independent people," Netanyahu said. "Not one of them is fake."
One Twitter user named in the report, Ziv Knobler, said in an interview with Israel's Army Radio that "there is nothing organized. We are a group of people who believe in the way of Benjamin Netanyahu."
"We expressed personal opinions, not on behalf of an organization," Knobler said. "We have absolutely no connection to the Likud party." After the Big Bots Project's report headlined Monday's edition of Hebrew daily Yedioth Ahronoth, Gantz's Blue and White party wrote on Twitter that "Netanyahu is trying to steal the elections" and called for a police investigation to determine the network's funding.
Last month, news broke that Gantz's personal telephone was infiltrated by Iranian hackers. While Gantz contends no sensitive information was compromised, Netanyahu leveraged the breach to argue that Gantz was unprepared to lead the country.