A trio of major media entities—The Associated Press, USA Today, and Vice Media—sued the FBI on Friday in an attempt to force the agency to reveal details from a mysterious deal that the agency struck in order to bust into a seized iPhone used by a now-deceased terrorist.

In April 2016, FBI Director James Comey suggested that his agency paid over $1.3 million to an unnamed company to unlock the iPhone 5C that was used by Syed Farook Rizwan, the man behind an attack in San Bernardino, California in December 2015.

The Department of Justice and Apple were set to square off in federal court in California in March 2016 before the hearing was called off. The government soon announced that it had been shown a new technique to unlock the phone and no longer needed Apple's help. The DOJ previously received a court order that would have compelled Apple to create an entirely new customized iOS to allow investigators to brute force the passcode on the device. Apple, for its part, forcefully argued that this was a significant government overreach.

According to the new lawsuit, the three companies had filed separate requests under the Freedom of Information Act to receive financial and contractual details of this deal—not the actual results of it. All of the requests, and the subsequent appeals, were denied.

The complaint continues:

Information about the FBI’s contracting arrangement would also ensure transparency about the expenditure of public funds. Understanding the amount that the FBI deemed appropriate to spend on the tool, as well as the identity and reputation of the vendor it did business with, is essential for the public to provide effective oversight of government functions and help guard against potential improprieties. Further, the public is entitled to know the nature of the vendors the Government finds it necessary to deal with in cases of access to private information, including whether or not the FBI feels compelled to contract with groups of hackers with suspect reputations, because it will inform the public debate over whether the current legislative apparatus is sufficient to meet the Government’s need for such information.

FBI spokesman Christopher Allen declined comment.

"As you recall, I am not able to comment on matters pending litigation," he e-mailed.