Turns out the FBI isn't the only agency to take over a child pornography website and bust some of its participants. Australian authorities have apparently employed similar tactics against Americans—revealing at least 30 targets.

According to Vice Motherboard, which first reported the story on Monday, Queensland Police Service’s Task Force Argos identified the owner of a Tor-hidden child porn site called “The Love Zone.” Queensland Police posed as The Love Zone for several months in 2014. (The Love Zone's Australian owner, Shannon McCoole, is currently serving a 35-year sentence.)

Once they had control, Aussie cops seem to have sent out a child porn video file as bait to users of the site.

As was explained in a court filing in a July 2015 case involving a North Carolina man named David Lynn Browning:

When a user clicked on that hyperlink, the user was advised that the user was attempting to open a video file from an external website. If the user chose to open the file, a video file containing images of child pornography began to play, and the [foreign law enforcement agency] captured and recorded the IP address of the user accessing the file. FLA configured the video file to open an Internet connection outside of the Network software, thereby allowing FLA to capture the user’s actual IP address, as well as a session identifier to tie the IP address to the activity of a particular user account.

Australian authorities obtaining a warrant to target Americans is potentially problematic from a legal perspective. If the situations were reversed, however, US judges have ruled that the Fourth Amendment does not apply overseas, and thus a warrant as defined by probable cause is not necessary.

The Aussie investigation into The Love Zone is distinct from the 135 US cases currently being prosecuted as a result of the FBI’s investigation of the Tor-hidden child pornography site known as “Playpen.” As Ars reported before, those cases involved the FBI deploying a "network investigative technique" (NIT) in order to breach the security normally afforded by Tor. In a related case prosecuted out of New York, an FBI search warrant affidavit described both the pornography available to Playpen’s 150,000 members and the NIT's capabilities.

In May 2016, a federal judge in Tacoma, Washington, threw out evidence in US v. Michaud. The judge found that the warrant originally issued by a magistrate judge in Virginia went too far. This was at least the third judge who has reached this conclusion.

These judges, who ruled in favor of the defendants, found that a Virginia magistrate's warrants to search the defendants' computers does not have force of law in other states. The warrants, according to the judges, are in violation of federal judicial procedure. Other judges, meanwhile, have said that the warrants are also invalid, but they did not go so far as to suppress evidence.

FBI spokesman Christopher Allen did not immediately respond to Ars' request for comment, but he told the following to Vice Motherboard: