Amnesty International says that the Israeli firm behind a recent security breach, which targeted human rights activists using the WhatsApp messenger app, must be held into account for its close ties with repressive regimes.

In a statement, Amnesty urged the Israeli regime to revoke export licenses of the notorious Israeli IT firm NSO, which designed the spyware linked to the WhatsApp breach.

The London-based rights group told Reuters that the company’s deeds “resulted in human rights abuses.”

PNN reports that WhatsApp, a unit of Facebook, admitted that hackers had managed to use the security breach on its messaging app to target human rights activists.

Eva Galperin, director of cybersecurity at San Francisco-based Electronic Frontier Foundation, said WhatsApp had informed human rights groups that the spyware was likely developed by Israel’s NSO. This was also confirmed by another person familiar with the matter.

In an emailed statement to Reuters, Amnesty asserted that NSO has “again and again demonstrated their intent to avoid responsibility for the way their software is used.”

It said only the Israeli regime at its highest ranks could intervene and stop the company.

NSO said, after the WhatsApp breach, that it would investigate any “credible allegations of misuse” of its technology which “is solely operated by intelligence and law enforcement agencies.”

WhatsApp, one of the world’s most popular messaging tools which is used by 1.5 billion people monthly, said it had fixed the exploit in its latest update and asked the US Department of Justice to help with an investigation into the breach.