Senior government officials in multiple countries were targeted earlier this year with hacking software that used WhatsApp to take over users’ phones, Reuters news agency quoted people familiar with the messaging company’s investigation.

Quoting WhatsApp’s internal investigation into the breach, the British news service reported that a significant portion of the known victims are high-profile government and military officials spread across at least 20 countries on five continents.

The hacking of a wider group of top government officials’ smartphones than previously reported suggests the WhatsApp cyber intrusion could have broad political and diplomatic consequences. WhatsApp filed a lawsuit against Israeli hacking tool developer NSO Group.

The Facebook-owned software giant said that NSO Group built and sold a hacking platform that exploited a flaw in WhatsApp-owned servers to help clients hack into the cellphones of at least 1,400 users. While it is not clear who used the software to hack officials’ phones, NSO says it sells its spyware exclusively to government customers.

Some victims are in the US, United Arab Emirates, Bahrain, Mexico, Pakistan, and India. The revelation comes as more than a dozen Indian journalists and human rights activists said they were also targeted. Previously, NSO has denied any wrongdoing, saying its products are only meant to help governments catch terrorists and criminals.

Over the last several years, cybersecurity researchers have found NSO products used against a wide range of targets, including protesters in countries under authoritarian rule. The use of these tools to target high-profile politicians, however, is less understood. CitizenLab, an independent research group working with WhatsApp, said at least 100 of the victims are journalists and dissidents, not criminals.

WhatsApp has said it sent warning notifications to affected users earlier this week. “It is an open secret that many technologies branded for law enforcement investigations are used for state-on-state and political espionage,” said John Scott-Railton, a senior researcher with CitizenLab.

Prior to notifying victims, WhatsApp checked the target list against existing law enforcement requests for information relating to criminal investigations, such as terrorism or child exploitation cases. But the company found no overlap. Governments can submit such requests for information to WhatsApp through an online portal the company maintains.