The Israeli government is setting up a commission of inquiry to investigate the police use of the Pegasus spyware without a court order to hack into the phones of dozens of civilians.
Among those targeted were the son of former prime minister Binyamin Netanyahu, a key witness in Mr Netanyahu's corruption trial, mayors, government officials, journalists and political activists.
Monday's explosive revelations in the Calcalist newspaper followed an earlier police denial that they had used the controversial spyware manufactured by the Israeli surveillance company NSO, which has made headlines in a number of countries after being sold to authoritarian governments.
The government had already instituted an export review after reports of misuse by foreign governments, including allegations of spying on civil rights activists and journalists in a number of countries.
One immediate result of the newspaper report was a decision by the Jerusalem district court to postpone the graft trial of Mr Netanyahu until the judges can determine the extent of illegal police spying against a key witness who was due to testify in the coming days.
Police hacked the phone of Mr Netanyahu's son Avner because they suspected that Sara Netanyahu, Binyamin's wife, used the device.
Prime minister Naftali Bennett promised that the revelations would not go unanswered.
“Pegasus and similar devices are important tools in the fight against terrorism and severe crime, but they were not intended to be used in phishing campaigns targeting the Israeli public or officials, which is why we need to understand exactly what happened,” he said.
Pegasus is considered one of the most powerful cyber-surveillance tools available on the market, providing operators with the ability to effectively take full control of a target’s phone, download all data from the device and activate its camera or microphone without the user knowing. The software was deployed by a special operations team inside the police’s cybersecurity unit.
The commission will be led by a retired judge and will be able to summon witnesses, investigate them and seize documents.
Israel's public security minister, Omer Bar Lev, stressed that the alleged violations occurred under previous governments and he promised a thorough investigation into all the allegations. However, civil rights groups argued that only a completely independent state commission of inquiry could examine the issue.
Interior minister Ayelet Shaked said the reports reminded her of how the Stasi operated in East Germany. "If these reports are true we are talking about an earthquake, acts suited to dark regimes from the previous century that we must not be like," she said. "Mass intrusion into the privacy of many people is lawlessness that must be stopped today."