In January, Motherboard reported on the FBI's "unprecedented" hacking operation, in which the agency, using a single warrant, deployed malware to over one thousand alleged visitors of a dark web child pornography site. Now, it has emerged that the campaign was actually several orders of magnitude larger.

In all, the FBI obtained over 8,000 IP addresses, and hacked computers in 120 different countries, according to a transcript from a recent evidentiary hearing in a related case.

The figures illustrate the largest ever known law enforcement hacking campaign to date, and starkly demonstrate what the future of policing crime on the dark web may look like. This news comes as the US is preparing to usher in changes that would allow magistrate judges to authorize the mass hacking of computers, wherever in the world they may be located.

"We have never, in our nation's history as far as I can tell, seen a warrant so utterly sweeping," federal public defender Colin Fieman said in a hearing at the end of October, according to the transcript. Fieman is representing several defendants in affected cases.

Those cases revolve around the FBI's investigation into dark web child pornography site Playpen. In February 2015, the FBI seized the site, but instead of shutting it down, the agency ran Playpen from a government server for 13 days. However, even though they had administrative control of the site, investigators were unable to see the real IP address of Playpen's visitors, because users typically connected to it through the Tor network.

In order to circumvent that anonymity, the FBI deployed what it calls a network investigative technique (NIT), or a piece of malware. That malware, which included a Tor Browser exploit, broke into the computer of anyone who visited certain child pornography threads on Playpen. It then sent the suspect's real IP address back to the FBI.

According to court filings, the FBI obtained over 1,000 IP addresses of alleged US-based users. Over the past year, Motherboard has also found that the FBI hacked computers in Australia, Austria, Chile, Colombia, Denmark, Greece, and likely the UK, Turkey, and Norway too.

But, those are only a tiny handful of countries in which the FBI was hacking computers. According to the newly published transcript, the FBI hacked computers in at least 120 countries.

"The fact that a single magistrate judge could authorize the FBI to hack 8000 people in 120 countries is truly terrifying," Christopher Soghoian, principal technologist at the American Civil Liberties Union (ACLU) told Motherboard in a phone call. (Soghoian has testified for the defense in Playpen cases).

Bizarrely, the FBI also hacked what has been described as a "satellite provider," according to the transcript.