Omar Abdulaziz, a friend of murdered Saudi journalist, Jamal Khashoggi has sued an Israeli software company he believes helped the Saudi government to intercept messages sent to him from people criticizing Mohammed bin Salman.

Abdulaziz, a Saudi national who now lives in exile in Canada, filed a lawsuit on Sunday against the NSO Group, alleging that its spyware helped the Saudi government gain access to his smart phone.

The lawsuit, filed in Tel Aviv, accused the Group of breaking international laws by selling its software, which allegedly allows its customers to secretly listen to calls and read messages on a targeted phone to oppressive regimes.

“The hacking of my phone played a major role in what happened to Jamal. I am really sorry to say. The guilt is killing me,” Mr. Abdulaziz said.

The Quebec-based Saudi activist reportedly exchanged messages with Khashoggi in the months leading to his death.

In the messages sent to Abdulaziz, Khashoggi called Salman, the Saudi Crown Prince and de-facto ruler of the kingdom a beast and likened him to a ‘Pac-Man’ who devours everything in his path

“The more victims he eats, the more he wants. I will not be surprised if the oppression will reach even those who are cheering him on,” Khashoggi said in one message sent in May, just after the arrest of a group of Saudi womens’ right activists.

According to messages seen by CNN, Khashoggi and the 27-year-old Abdulaziz began to talk about plans to form an ‘electronic army’ of young Saudis living in the country to try to undermine the government’s online propaganda.

In early August, Abdulaziz discovered that the Saudi government was aware of their project. Two months after the discovery, Khashoggi was killed in the Saudi consulate in Istanbul, Turkey.

Last month, Abdulaziz revealed that researchers at the University of Toronto’s Citizen Laboratory reported that his phone had been hacked by military-grade spyware. According to them, the software was the invention of NSO Group which was deployed at the behest of the Saudi government.

The NSO Group has previously faced lawsuits from citizens from Mexico and Qatar, who alleged that the technology was used to hack their smart phones. The Amnesty International has also recently accused the NSO Group of helping Saudi Arabia spy on a member of the organization’s staff.

The NSO Group has however issued a statement, saying that the technology, which has helped many governments to fight crime was fully vetted and licensed by the Israeli government.

“Our products have a long track record of assisting governments in preventing suicide bombers, stopping drug lords and sex traffickers and helping safely return victims of kidnapping,” the statement said.

“If there is suspicion of misuse, we investigate it and take the appropriate actions, including suspending or terminating a contract,” the statement read.