Italian prosecutors are investigating six former employees of surveillance software maker Hacking Team in connection with the massive attack on the systems of the Italian cybersecurity firm.
Hackers last week published over 400 gigabytes of data from the firm, which makes software that allows law enforcement and intelligence agencies to tap into the phones and computers of suspects.
The data included thousands of private corporate emails, client lists, invoices and product source code.
Investigative sources said the six suspects had already been placed under investigation in a separate case for allegedly revealing the company's industrial secrets.
That probe was launched after Hacking Team CEO David Vincenzetti filed a complaint in May accusing the six former employees of having revealed part of the company's source code, according to the sources.
The two investigations have now been combined.
A Hacking Team spokesman did not immediately respond to request for comment.
The leaked emails show Hacking Team worked with numerous state institutions in an array of countries, including Italy, the United States and Australia. Its customers include the US Federal Bureau of Investigation and Australian Federal Police, according to the leaked data.
It also had dealings with countries criticised for their human rights records, such as Libya, Egypt, Ethiopia, Kazakhstan, Morocco, Nigeria, Saudi Arabia and Sudan.
Vincenzetti has previously said a government might have been behind the hacking of the company's systems.