Apple and the FBI might be on a collision course yet again.
Speaking at a press conference in St. Cloud, Minn. on Friday, FBI special agent Rich Thorton said that the law-enforcement agency is unable to unlock an iPhone recovered from Dahir Adan, the attacker who stabbed 10 people in a Minnesota mall last month. ISIS took responsibility for the attack after Adan was killed by an off-duty police officer.
According to Wired, which earlier reported on Thorton's comments, the FBI special agent told reporters that the FBI is currently evaluating "legal and technical options" to determine how it can gain access to the smartphone and ultimately retrieve its data.
The comments sound like preparation for what could be another legal battle between Apple and the FBI.
Earlier this year, the Justice Department filed a lawsuit against Apple (aapl), seeking the company's help in unlocking the iPhone 5c used by San Bernardino attacker Syed Farook. Apple declined the request even after a judge said it would need to create software to let the FBI unlock the smartphone. In an open letter, Apple CEO Tim Cook argued that user privacy was at risk and opening one iPhone could open the floodgates to the FBI accessing other users' smartphones. He added that he was willing to take the fight to the U.S. Supreme Court.
While the FBI and its director James Comey came down on Apple's unwillingness to unlock the smartphone, it found a way around the passcode by enlisting the help of an unidentified third party. It's believed the FBI paid $1 million for the hack, which allowed it to gain access to the smartphone and all of its data. The Justice Department then dropped its case against Apple.
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However, the fight was one that drew clear lines between law enforcement and its supporters, and privacy advocates. Those in law enforcement argued that Apple's move could put people around the world at risk, arguing that not giving the FBI access to terrorist data could leave the agency in the dark about a future attack. Apple and its supporters, however, noted that the FBI could do its police work in other ways, and providing a tool for hacking a smartphone could run afoul of personal rights and privacy.
With the prospect of the case being litigated in the highest court in the U.S., both sides had hoped to come to some sort of conclusion. Once the FBI found a way around the passcode, however, such hopes were shot down.
Now, the possibility of a fight between Apple and the FBI have reemerged. Accessing Adan's data requires inputting the correct passcode or hacking the handset. Too many failed attempts at cracking the code and the iPhone will lock the FBI out of the device, limiting its chances at trying different codes. Accessing the data, then, requires either Apple's help, a stroke of luck, or another third-party to step up and find a way in.
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Judging by its stance earlier this year, Apple is unlikely to stand up, leaving the FBI with the latter two possibilities. It's unknown, however, if any company or hacker knows a way in.
In addition to the iPhone, Thorton said that the FBI has already "analyzed more than 780 gigabytes of data from multiple computer and other electronic devices," according to Wired. It's also reviewed his social media accounts and "other online activity."
Neither the FBI nor Apple immediately responded to a Fortune request for comment.