But the report did not include any evidence that the network was being operated by Likud or Mr Netanyahu.
Likud denied having any control over the accounts and claimed that they were real people supporting the prime minister.
In a press conference, Mr Netanyahu hit back, appearing alongside Giora Ezra, the owner of one of the accounts who tweets as @CaptainGeorge8.
“Are you a bot? Are you real?” Mr Netanyahu asked. “It’s such a great lie, so transparent.”
Opposition parties Labour and Blue & White demanded the electoral commission investigate the alleged network.
However, whether or not the network is real and operated by someone to help the Likud campaign, it is unlikely to have had much of an influence. Twitter use in Israel is not especially high at around 17 per cent of those on the internet, equating to about a quarter-million regular users.
Cybersecurity experts are warning that the main online attempt to manipulate the election next week on April 9 is likely to be through text messages and WhatsApp groups, which could be used to anonymously spread fake information.
Likud campaigners acknowledged in the wake of the previous election in 2015 they had bombarded wavering right-wing voters with millions of text messages, making false claims about the turnout in the Arab sector.
This is supposed to have helped the surge in the Likud vote in the last hours of voting.
