Hacking Team, an Italian company that makes surveillance software used by governments to police the Internet, appeared to be the victim of hacking on a grand scale itself on Monday.
The 12-year-old Milan-based company, which describes itself as a maker of lawful interception software used by police and intelligence services worldwide to tap into online communications, has been accused by anti-surveillance campaigners of selling snooping tools to governments with poor human rights records.
Hacking Team found its Twitter account hijacked on Monday and used by hackers to release what is alleged to be more than 400 gigabytes of the company's internal documents, email correspondence, employee passwords and the underlying source code of its products.
"Since we have nothing to hide, we're publishing all our emails, files and source code," read posts published on the company's hijacked Twitter account. They were subsequently deleted.
Among the documents unearthed and published by the unknown hackers was a spreadsheet that purports to show the company's active and inactive clients at the end of 2014.
Those listed included police agencies in several European countries, the FBI and Drug Enforcement Administration in the United States and police and state security organizations in countries with records of human rights abuses, including Egypt, Ethiopia, Kazakhstan, Morocco, Nigeria, Saudi Arabia and Sudan.
Sudan's National Intelligence Security Service was one of two customers in the client list given the special designation of "not officially supported."
However, a second document — an invoice for $53,0616 to the same security service — calls into question repeated denials by the Hacking Team that it has done business with Sudan.
Hacking Team did not respond to emails or calls seeking to confirm the veracity of the documents. In a previous statement in March, the company said it could not disclose its clients "since to do so could jeopardize ongoing law enforcement investigations."
The company was singled out in 2012 as one of five private-sector "corporate enemies of the Internet" in a report by Reporters Without Borders.
Citizen Lab, a digital rights research group loosely affiliated with the University of Toronto, has published numerous reports linking Hacking Team software to alleged repression of minority and dissident groups and journalists in a number of countries in Africa and the Middle East.